Net Operating Losses: Proposed Extension of 
Carryback Period 
Mark P. Keightley 
Analyst in Public Finance 
November 13, 2009 
Congressional Research Service
7-5700 
www.crs.gov 
RL34535 
CRS Report for Congress
P
  repared for Members and Committees of Congress        
Net Operating Losses: Proposed Extension of Carryback Period 
 
Summary 
A net operating loss (NOL) is incurred when a business taxpayer has negative taxable income. An 
NOL can be used to obtain a refund for taxes paid in the past and/or to reduce future tax 
obligations. The process of using an NOL to refund previously paid taxes is known as an NOL 
carryback, whereas the process of using an NOL to reduce future taxes is known as a 
carryforward. Under current law, there is a 2-year carryback period and a 20-year carryforward 
period for most business taxpayers. 
In the 111th Congress, the American Recovery and Reinvestment Act of 2009 (H.R. 1, P.L. 111-5), 
provided business taxpayers with $15 million or less in gross receipts an opportunity to extend 
the carryback period for up to five years for NOLs incurred in 2008. More recently, the Worker, 
Homeownership, and Business Assistance Act of 2009 (P.L. 111-92) extended the carryback 
period to five years for all business taxpayers except those who have received certain federal 
assistance relating to the financial crisis. A taxpayer can use the extended carryback period for an 
NOL incurred in 2008 or 2009, but not both. The amount of loss that can be carried back to the 
fifth year is limited to 50% of the taxpayer’s taxable income in the fifth carryback year. This 
limitation, however, does not apply to businesses with $5 million or less in gross receipts that 
make a five-year carryback election after enactment of the bill. 
The intent of the NOL carryback/carryforward provision is to give taxpayers the ability to smooth 
out changes in business income, and therefore taxes, over the business cycle. Extending the 
carryback period would enhance the ability of firms to smooth income by allowing losses to be 
offset against a longer period of past profits rather than having them carried forward. The 
extension would, however, increase revenue losses to the federal government. 
Economic theory suggests that, under certain conditions, extending the carryback period 
indefinitely could minimize the distorting effects taxation has on investment decisions and, in 
turn, increase economic efficiency. This result stems from the observation that the majority of the 
tax burden falls on risky investments. The government, by allowing NOL carrybacks, effectively 
enters into a partnership with taxpayers when losses are allowed to be carried back, sharing both 
the return to investment (tax revenue) and the risk of investment (revenue loss). Extending the 
carryback period indefinitely would reduce the tax burden by reducing the private risk associated 
with investing. Further gains in economic efficiency are possible if the government can spread 
risk better than can be done in private markets. Those gains, however, come at the expense of lost 
federal revenue. 
This report explains the current law and proposed legislation regarding the tax treatment of 
NOLs. In addition, this report highlights a number of policy considerations relating to the 
extension of the NOL carryback period. This report will be updated in the event of legislative 
changes. 
Congressional Research Service 
Net Operating Losses: Proposed Extension of Carryback Period 
 
Contents 
Overview .................................................................................................................................... 1 
Legislative Developments ........................................................................................................... 2 
Policy Considerations ................................................................................................................. 3 
Economic Efficiency............................................................................................................. 3 
Economic Stimulus ............................................................................................................... 4 
Conclusion.................................................................................................................................. 5 
 
Tables 
Table A-1. Net Operating Loss Example...................................................................................... 7 
 
Appendixes 
Appendix A. NOL Carryback ...................................................................................................... 7 
Appendix B. Present Values ........................................................................................................ 8 
Appendix C. Paying Interest on NOL Carryforwards ................................................................... 9 
 
Contacts 
Author Contact Information ...................................................................................................... 10 
 
Congressional Research Service 
Net Operating Losses: Proposed Extension of Carryback Period 
 
axpayers experience a net operating loss (NOL) when their taxable business income is 
negative. The year in which an NOL occurs is called the NOL year, or loss year. Taxpayers 
T have no tax liability in the year that they experience an NOL. An NOL can be used, 
however, to obtain a refund for taxes paid in prior years and/or to reduce future tax liabilities. 
Using an NOL to refund past taxes paid is known as an NOL carryback. Applying an NOL to a 
future tax liability is referred to as an NOL carryforward (or carryover). According to the Joint 
Committee on Taxation, the intent of the NOL carryback/carryforward provision is to give 
taxpayers the ability to smooth out changes in business income, and therefore taxes, stemming 
from the business cycle and unexpected financial losses.1 
In the 111th Congress, the American Recovery and Reinvestment Act of 2009 (H.R. 1, P.L. 111-5), 
provided business taxpayers with $15 million or less in gross receipts an opportunity to extend 
the carryback period for up to five years for NOLs incurred in 2008. More recently, the Worker, 
Homeownership, and Business Assistance Act of 2009 (P.L. 111-92) extended the carryback 
period to five years for all business taxpayers except those who have received certain federal 
assistance relating to the financial crisis. A taxpayer can use the extended carryback period for an 
NOL incurred in 2008 or 2009, but not both. The amount of loss that can be carried back to the 
fifth year is limited to 50% of the taxpayer’s taxable income in the fifth carryback year. This 
limitation, however, does not apply to businesses with $5 million or less in gross receipts that 
make a five-year carryback election after enactment of the bill. 
This report explains the current law regarding the tax treatment of NOLs. In addition, this report 
highlights a number of policy considerations relating to the extension of the NOL carryback 
period. 
Overview 
In general, a taxpayer with an NOL can carry it back to the 2 taxable years preceding the NOL 
year, and/or carry it forward to each of the 20 taxable years following the NOL year.2 An NOL 
may not be used to offset more than 90% of a taxpayer’s alternative minimum taxable income 
(AMTI) in any one year. The Internal Revenue Code lists several exceptions to the general 2-year 
carryback/20-year carryforward provision.3 For example, losses as a result of casualty, theft, or a 
presidentially declared disaster are eligible to be carried back three years. Farming losses may be 
carried back five years. The portion of an NOL due to a specified liability loss may be carried 
back to the 10 years preceding the loss year.4 Real estate investment trusts (REITs) are not 
allowed to carry an NOL back, but are entitled to carry a loss forward up to 20 years. 
Current law stipulates that an NOL is to be first carried back to the two years preceding the loss 
year, beginning with the earliest year first. If the carryback does not fully exhaust the NOL, the 
remaining portion is then carried forward to the 20 years following the loss years. To take 
                                                             
1 U.S. Congress, Joint Committee on Taxation, General Explanations of Tax Legislation Enacted in the 107th Congress, 
committee print, 107th Cong., 2nd sess. (Washington: GPO, 2003), p. 220. 
2 Internal Revenue Code (IRC) § 172(b). 
3 The complete list can be found in IRC § 172(b)(1). 
4 Examples of specified liability losses include the expense incurred in the investigation or defense against a claim of 
product liability, a deduction due to reclamation of land, or certain costs attributable to the remediation of 
environmental contamination. 
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Net Operating Losses: Proposed Extension of Carryback Period 
 
advantage of an NOL a taxpayer must file either an amended income tax return, or an application 
for tentative refund.5 The taxpayer would use the appropriate form to first recalculate his or her 
tax liability for the earliest eligible carryback year. This calculation involves claiming the NOL as 
part of that year’s tax deductions. The taxpayer then receives, as a refund, the difference between 
the actual taxes paid in the previous year, and the new tax liability resulting from the NOL 
carryback.6 
Although the procedure is for an NOL first to be carried back to the earliest carryback year and 
then applied to each successive year, a taxpayer may irrevocably waive the carryback period. The 
NOL is then carried forward in a manner similar to the one described above. A taxpayer expecting 
to be in a considerably higher tax bracket in the future may find it beneficial to only carry an 
NOL forward. In general, however, a taxpayer will prefer to carry back an NOL rather than carry 
it forward. A carryback allows an immediate benefit of the amount of the refunded tax payment, 
whereas a carryforward reduces future taxes whose value must be discounted to the present. The 
need to discount a future tax reduction due to an NOL carryforward results in the present value of 
an NOL carryback exceeding the present value of an NOL carryforward.7 A carryback, 
additionally, provides a certain tax refund whereas a carryforward reduces a tax liability at some 
potentially uncertain time in the future. 
Legislative Developments 
The current regime of a 2-year carryback period and a 20-year carryforward period was instituted 
in 1997 with the Taxpayer Relief Act of 1997 (P.L. 105-34). Prior to that time, NOLs were subject 
to a 3-year carryback and a 15-year carryforward. The Omnibus Budget Reconciliation Act of 
1990 (P.L. 101-508) increased the NOL carryforward period from 7 to 15 years. 
Since 1997, changes to the carryback period have either involved temporary extensions or 
targeted provisions. For example, in the 105th Congress, the Tax and Trade Relief Act of 1998 
(P.L. 105-277) permanently extended the NOL carryback period for losses relating to farming to 
five years. The 107th Congress temporarily extended the NOL carryback period from two to five 
years for losses incurred in 2001 and 2002 as part of the Job Creation and Worker Assistance Act 
of 2002 (P.L. 107-147). The extension, designed to provide tax incentives for economic recovery, 
also allowed NOL carrybacks and carryovers to offset up to 100% of a business’s AMTI. 
The 109th Congress passed the Gulf Opportunity Zone Act of 2005 (P.L. 109-135) in response to 
the destruction caused by Hurricanes Katrina, Rita, and Wilma. The act extended the carryback 
period from two to five years for qualified losses occurring in the Gulf Opportunity Zone (or GO 
Zone). In addition, the act expanded the list of acceptable deductions used for determining NOLs 
in the Go Zone, effectively increasing the amount of losses a taxpayer could recover. 
                                                             
5 IRS Forms 1120X and 1040X are the amended income tax returns for corporations and individuals, estates, and trusts, 
respectively. The appropriate applications for a tentative refund for corporations and individuals, estates, and trusts are 
IRS Forms 1139 and 1045, respectively. 
6 A practical illustration is useful to show how an NOL carryback works; one can be found in Appendix A. 
7 The present value of future cash flows reflects the time value of money (i.e., why a dollar received today is more 
valuable than a dollar received in the future). Appendix B explains the concept of present values. Also contained in 
Appendix B is an example computing the present value of an NOL carryback and an NOL carryforward. 
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Net Operating Losses: Proposed Extension of Carryback Period 
 
In the 110th Congress a number of bills were introduced that would have extend the NOL 
carryback period. Early versions of the Housing and Economic Recovery Act of 2008 (H.R. 
3221) included proposals to extend the carryback period to up to four years. The final version of 
H.R. 3221 that became law (P.L. 110-289) left the carryback period unchanged. 
The Small Business Stimulus Act of 2008 (S. 2552 and S. 2553) would have allowed NOLs 
incurred in 2007 and 2008 to be carried back five years. The 90% AMTI carryback and carryover 
limitation for NOLs would also be suspended for losses in those two years. 
The Midwestern Disaster Tax Relief Act of 2008 (S. 3322 and H.R. 6587) proposed to extend the 
two-year NOL carryback period to four years for qualified disaster areas affected by recent severe 
weather in the Midwest. The 90% AMTI limitation would also be waived for qualified disaster 
losses. 
In the 111th Congress, the American Recovery and Reinvestment Act of 2009 (H.R. 1, P.L. 111-5), 
provided business taxpayers with $15 million or less in gross receipts an opportunity to extend 
the carryback period for up to five years for NOLs incurred in 2008. More recently, the Worker, 
Homeownership, and Business Assistance Act of 2009 (P.L. 111-92) extended the carryback 
period to five years for all business taxpayers except those who have received certain federal 
assistance relating to the financial crisis. A taxpayer can use the extended carryback period for an 
NOL incurred in 2008 or 2009, but not both. The amount of loss that can be carried back to the 
fifth year is limited to 50% of the taxpayer’s taxable income in the fifth carryback year. This 
limitation, however, does not apply to businesses with $5 million or less in gross receipts that 
make a five-year carryback election after enactment of the bill. 
The Joint Committee on Taxation (JCT) estimates that the modifications introduced by the 
Worker, Homeownership, and Business Assistance Act of 2009 will cost $10.4 billion for FY2010 
through FY2019.8 
Policy Considerations 
As mentioned above, the current Congress and the previous Congress have both introduced 
legislation that would or has addressed the treatment of NOLs. The following considerations 
could be helpful to policy makers interested in future changes to the treatment of NOLs. The 
discussion below distinguishes between the tax treatment of NOLs as a method to enhance 
economic efficiency, and the use of NOL carrybacks to stimulate economic activity. 
Economic Efficiency 
The intent of the NOL carryback/carryforward provision is to give taxpayers the ability to smooth 
out changes in business income, and therefore taxes, over the business cycle. Increasing the 
fraction of AMTI that may be offset using an NOL from 90% to 100% would promote income 
smoothing by allowing taxpayers to fully recover current losses now, as opposed to in the future. 
In addition, extending the carryback period would enhance the ability to smooth income by 
                                                             
8  U.S. Congress, Joint Committee on Taxation, Estimated Revenue Effects Of Certain Revenue Provisions Contained 
In The “Worker, Homeownership, And Business Assistance Act Of 2009”, committee print, prepared by JCT, 111th 
Cong., 1st sess., November 3, 2009, JCT-45-09 (Washington: GPO, 2009). 
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Net Operating Losses: Proposed Extension of Carryback Period 
 
allowing losses to be offset against a longer period of past profits rather than having them carried 
forward. The extension would, however, increase revenue losses to the federal government. As 
previously mentioned, carrybacks are more valuable than carryforwards due to the time value of 
money (i.e., a dollar today is more valuable than a dollar in the future). 
Economic theory suggests that, under certain conditions, extending the carryback period 
indefinitely would minimize the distorting effects taxation has on investment decisions and, in 
turn, increase economic efficiency.9 This result stems from the observation that the majority of the 
tax burden falls on risky investments. The government effectively enters into a partnership with 
taxpayers when losses are allowed to be carried back, sharing both the return to investment (tax 
revenue) and the risk of investment (revenue loss). Extending the carryback period indefinitely 
would reduce the tax burden by reducing the private risk associated with investing. Further gains 
in economic efficiency are possible if the government can spread risk better than private markets. 
The need to minimize revenue losses introduces some practical limitations that prevent the 
indefinite carryback of NOLs. Some economists believe that allowing indefinite carrybacks 
would result in a large negative revenue effect, particularly during an economic downturn.10 
Others have noted that encouraging investors to undertake risky investments is generally highly 
desirable, except in periods of acute economic boom.11 It could be argued that in an extremely 
expansionary period investors are already making sufficiently risky investments and that adding 
further incentives to take on more risk is unnecessary. 
Although an indefinite carryback period may be practically infeasible, most economists agree that 
the NOL carryback period must be long enough to allow for adequate income smoothing and an 
efficient degree of investment-risk reduction over the business cycle. 
Since World War II the duration of the average business cycle has been approximately six years. 
Extending the NOL carryback period to at least the length of the typical business cycle would, 
arguably, allow for more income smoothing and risk reduction. Income smoothing and risk 
reduction could also be enhanced by paying interest on losses carried forward.12 
Economic Stimulus 
Some economists believe that extending the NOL carryback period during an economic downturn 
could stimulate business investment, an important component of economic growth. Businesses on 
the margin of profitability may choose to speed up investments planned for the future. By 
investing now, a firm’s tax-related deductions resulting from the investment may result in an 
NOL, which can be used to receive a refund for previously paid taxes. Along the same line, an 
extended NOL carryback period may increase the stimulative effect of more targeted tax-related 
investment incentives such as bonus depreciation. 
                                                             
9 Evsey D. Domar and Richard A. Musgrave, “Proportional Income Taxation and Risk-Taking,” The Quarterly Journal 
of Economics, vol. 58, May 1944, p. 388. 
10 Andrew Weiss, “A Tax Reform to Alleviate Recessions and Reduce Biases in the Tax Code,” Boston University 
Working Paper, Jan. 1999. 
11 Domar and Musgrave, “Proportional Income Taxation and Risk-Taking,” p. 391. 
12 Appendix C presents an example of NOL carryforwards that accrue interest. 
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Net Operating Losses: Proposed Extension of Carryback Period 
 
Additionally, businesses experiencing large current losses could apply their losses over a longer 
profitable period in the past, resulting in a more immediate refund of taxes paid than would have 
otherwise been possible. The refund could provide businesses that are unable to raise capital in 
financial markets with enough extra cash to pursue profitable investment opportunities. The 
current lack of available credit stemming from events in the subprime mortgage market that have 
spilled over into other segments of the financial markets could be one reason why it may be 
difficult for some to secure investment financing. 
Other economists have argued that some businesses are unable to raise capital needed to make 
new investments because profitable investment opportunities are limited as a result of the recent 
slowdown in economic activity. Firms could be inclined to hold onto any increase in cash 
resulting from larger NOL carryback refunds if rewarding investment opportunities do not appear. 
Uncertainty over the current path of the economy may further exacerbate the desire of some firms 
to hold cash and invest it at a later date. Businesses that lack profitable investment projects may 
choose to instead use a cash inflow resulting from a larger NOL carryback refund to cover 
operating expenses such as employee wages. As a result, extending the carryback period could 
have a positive effect on employment, although in the short-run the effect could be overshadowed 
by more general economic weakness. 
The Congressional Budget Office (CBO) has attempted to quantify the stimulative effect on the 
nation’s gross domestic product (GDP) of extending the NOL carryback period.13 CBO estimates 
that every $1.00 in NOL carrybacks translates into a GDP increase of between $0 and $0.40. In 
comparison, the CBO estimates that a $1.00 increase in federal government purchases increases 
GDP by between $2.50 and $1.00, while a well-targeted temporary $1.00 reduction in individual 
taxes increases GDP by between $0.50 and $1.70. 
It has been noted by some that an extension of the carryback period would tend to benefit older 
businesses over newer businesses.14 Older businesses that are currently experiencing losses, but 
that have been profitable in the years included in the proposed extended carryback window, will 
receive an immediate and certain tax refund. New firms, on the other hand, do not necessarily 
have a long past of profitable years to which NOLs can be carried back. These younger firms can 
therefore only carry losses forward. But carryforwards are valued less than carrybacks because a 
carryforward must be discounted, and also because its benefit depends on the realization of 
income at some uncertain point in the future. Thus, the benefits of the proposed carryback 
legislation would tend to accrue to older businesses. 
Conclusion 
Policy makers face a number of trade-offs when addressing the desirability of an extension of the 
NOL carryback period. A longer carryback period would reduce the tax burden on business 
taxpayers by reducing private risk and promoting income smoothing and, as a result, increase 
economic efficiency. On the other hand, the revenue effect on the federal budget will be larger the 
longer losses are allowed to be carried back. 
                                                             
13  U.S. Congress, House Committee on the Budget, The State of the Economy and Issues in Developing an Effective 
Policy Response, The Economic Outlook and Budget Challenges, 111th Cong., January 27, 2009. 
14 Benzion Barlev and Haim Levy, “Loss Carryback and Carryover Provision: Effectiveness and Economic 
Implications,” National Tax Journal , vol. 28, June 1975, p. 173. 
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Net Operating Losses: Proposed Extension of Carryback Period 
 
In the short-run, extending the NOL carryback period will provide some business investors with 
an influx of cash, but it does not guarantee that these taxpayers will use the cash to pursue new 
stimulative investment opportunities. If attractive investment opportunities exist in the economy, 
then allowing businesses access to previously paid taxes may result in the undertaking of new 
investment. On the other hand, if there is a large degree of economic uncertainty businesses will 
likely hold on to any NOL tax refund. In this case, the stimulative effects would diminish. 
Another issue is determining the optimal carryback and carryover period lengths. A two-year 
carryback period is relatively short compared to the average post World War II business cycle of 
around six years. A longer carryback period may increase the ability to smooth income over the 
business cycle. However, it is also important to keep in mind the trade-offs previously discussed 
when considering an expansion of the carryback period, particularly the potential increase in 
federal revenue loss. 
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Appendix A. NOL Carryback 
The following example illustrates the basic calculations involved in carrying back an NOL, and 
the mechanism through which an NOL carryback allows for smoothing of income. Table A-1 
illustrates two firms whose total business income, costs, and taxable income are similar over a 
two-year period. The firms differ, however, in the timing of their annual income and costs. It is 
assumed that both firms face a 35% corporate income tax. 
Firm A’s taxable income in each year is $25 million. Therefore, each year Firm A pays $8.75 
million in corporate income taxes, for a total two-year tax liability of $17.5 million. Firm A has 
no NOL in either year so its tax liability with and without NOL carrybacks is the same. 
Firm B has taxable income equal to $75 million in year one, but incurs an NOL equal to $25 
million in year two. Firm B must pay $26.25 million in taxes in year one. If Firm B is not 
permitted to carryback its year-two NOL, its total two-year tax liability will equal taxes paid in 
year one; $26.25 million. On the other hand, if Firm B is allowed to carryback its year-two NOL, 
it will be able to receive a partial refund for taxes paid in year one. 
To receive the refund Firm B will recalculate its year-one tax liability by subtracting its $25 
million NOL in year two from its $75 million year-one taxable income and applying the 35% 
corporate income tax rate. The recalculated year-one tax liability is found to be $17.5 million 
($50 million × 35%). Firm B is then entitled to receive, as a refund in year two, the difference 
between its taxes actually paid in year one, and the new recalculated tax liability. The refund paid 
to the firm in year two as a result of its NOL is calculated to be $8.75 million ($26.25 million - 
$17.5 million). 
Allowing Firm B the opportunity to carry back its NOL allowed it to smooth income. As a result 
both firms had the same total two-year tax liability, in-line with both firms having the same total 
two-year taxable income. 
Table A-1. Net Operating Loss Example 
(in millions of dollars) 
 Firm 
A 
Firm B 
 
Yr 1 
Yr 2 
Total 
Yr 1 
Yr 2 
Total 
Business Income 
$150 
$150 
$300 
$150 
$150 
$300 
Costs and Deductions 
$125 
$125 
$250 
$75 
$175 
$250 
Taxable 
Income 
 
$25  $25 $50 $75 ($25) 
$50 
Tax without NOL carryback  
$8.75 
$8.75 
$17.5 
$26.25 
- 
$26.25 
Tax with NOL carryback 
$8.75 
$8.75 
$17.5 
$26.25 
(8.75) 
$17.5 
Source: CRS calculations. 
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Net Operating Losses: Proposed Extension of Carryback Period 
 
Appendix B. Present Values 
The concept of present value is essential to understanding the time value of money (i.e., why a 
dollar received today is more valuable than a dollar received in the future). Money received at 
different points in time is valued differently because of the opportunity to earn a return on money 
received earlier. As a result, taxpayers will usually prefer to carry back an NOL (and receive 
income in the present year), rather than carry it forward (and wait to receive income in the 
future). 
To see this, consider a taxpayer that must decide between an NOL carryback and an NOL 
carryforward. For simplicity, it is assumed that the taxpayer can either receive a tax refund today 
equal to $10 million from carrying back the NOL, or reduce taxes owed next year by $10 million 
by carrying the NOL forward. It is also assumed that the annual rate of return on investment is 
10%. 
By choosing to carryback the NOL, the taxpayer receives $10 million today which could be 
invested to earn a 10% return. On the other hand, the taxpayer forgoes the opportunity to such a 
return if they choose to carry the NOL forward. Thus, the taxpayer will prefer to carry the NOL 
back rather than carry it forward. An economist would say that the present value of the NOL 
carryback is greater than the present value of the NOL carryforward. 
The formula for calculating the present value (PV) of $X to be received N years in the future is 
$ X
PV =
 
(1 + r N
)
where r is the return on investment (e.g., an interest rate). When the rate of return is 10%, the PV 
of a $10 million carryforward tax rebate that is to be received in one year is 
$10 million
PV =
 
1
= $9.1million
(1 + r)
Therefore, $10 million received in one year is equivalent to $9.1 million received today. But the 
present value of a $10 million carryback tax refund, which is received today, is simply $10 
million. Thus, it is preferable to carry back an NOL in order to receive money today, rather than 
to carry it forward to reduce future taxes. 
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Appendix C. Paying Interest on NOL Carryforwards 
Some economists have suggested that NOL carryforwards should earn interest. This could benefit 
taxpayers unable to fully exhaust their NOLs through carrybacks. As mentioned previously in the 
report, new firms may not have enough years of past profitability to fully take advantage of an 
NOL carryback. Allowing interest to accrue on carryforwards could reduce the discrepancy 
between the NOL tax treatment of new and old firms. 
Continuing with the previous example, assume that a taxpayer can either receive a tax refund 
today equal to $10 million from carrying back an NOL, or reduce taxes owed next year by $10 
million by carrying an NOL forward. Again it is assumed that the rate of return on investment is 
10%. Now, however, assume that the government pays interest on carryforwards equal to the 
taxpayer’s rate of return on investment. Thus, a $10 million rebate from a carryforward that earns 
10% interest will be worth $11 million in one year. 
Recall that the formula for calculating the present value (PV) of $X to be received N years in the 
future is 
$ X
PV =
 
(1 + r N
)
where r is the interest rate. When the interest rate is 10%, the PV of a $10 million carryforward 
tax rebate that earns 10% interest and will be received in one year is 
$10 million × .
110
PV =
= $10million  
( .
11 )
0 1
Therefore, a $10 million carryforward that earns 10% interest and that will be received in one 
year is equivalent to $10 million received today. Recall that the present value of a $10 million 
carryback tax refund, which is received today, is simply $10 million. Thus, when NOL 
carryforwards earn interest they will have the same present value as a carryback. In this example 
taxpayers will be indifferent between a carryback and a carryforward. 
The example above assumes that a firm’s rate of return on investment is equal to what the 
government would pay in interest. It is likely the government would use a Treasury rate to 
determine the interest paid on NOL carryforwards. The present value of an NOL carryforward 
would be less than an equal NOL carryback if the interest rate paid on carryforwards by the 
government were less than the firm’s rate of return on investment. On the other hand, the present 
value of a carryforward would exceed that of an equal carryback if the government’s interest rate 
were greater than the firm’s rate of return on investment. 
 
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Author Contact Information 
 
Mark P. Keightley 
   
Analyst in Public Finance 
mkeightley@crs.loc.gov, 7-1049 
 
 
 
 
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