Accrual vs Cash Accounting: Methods, Limits, and Form 3115

The choice between cash vs accrual accounting comes down to timing: cash accounting reports income and expenses when money actually moves, while accrual accounting reports them when they are earned or incurred, whether or not payment has changed hands. Most small businesses can pick either one for federal tax purposes if they average $32 million or less in annual gross receipts over the prior three years. Above that threshold, and for certain entity types regardless of size, accrual is mandatory.¹

Your method decides when income lands on a return and when a deduction is available, which in turn drives how much tax you owe in any given year.

How Cash Accounting Works

Under the cash method, you report income when you receive payment and deduct expenses when you pay them. Bookkeeping is simpler, and your books track your actual bank balance closely. What they won’t show is money customers owe you or bills you haven’t paid.

The IRS uses a concept called constructive receipt to keep taxpayers from deferring income artificially. Income counts as received when it is credited to your account, set aside for you, or otherwise made available without substantial restrictions.² A check that arrives December 31 is current-year income even if you deposit it in January. Whether you had access to the funds is what matters, not whether you touched them.

Within those limits, cash accounting offers real timing flexibility. You can prepay a January bill in December to accelerate a deduction, or hold off on sending an invoice until January to push income into the next year. Accrual-method businesses lose that lever.

How Accrual Accounting Works

Accrual accounting reports income when you earn it and expenses when you incur them. Deliver a product in November and get paid in February, and the revenue belongs to November. Receive supplies in October and pay the vendor in January, and the deduction belongs to October. The point is to match revenue against the expenses that produced it in the same period.

The All-Events Test

The IRS uses the all-events test to fix the year an item belongs on the return. For income, the test is satisfied when you have done everything required to earn the payment and the amount can be determined with reasonable accuracy. For expenses, all events creating the obligation must have occurred and the amount must be reasonably determinable.²

Economic Performance

Passing the all-events test isn’t enough on the expense side. Under Section 461(h), economic performance also has to occur. If someone provides services or property to you, economic performance happens as they deliver. If you owe an obligation to provide services or property to someone else, economic performance happens as you deliver. For tort and workers’ compensation liabilities, economic performance occurs only when you actually pay.³

Prepaying a two-year service contract in full doesn’t produce a full deduction up front. You deduct each year’s share as the services are actually performed.

Advance Payments You Receive

Accrual-method businesses that collect payment before delivering can either report the full advance as income in the year of receipt or elect to defer the portion tied to goods or services that will be delivered in the following year. The deferral is capped at one year. Any amount not included in the year of receipt has to be included the very next tax year, even if you won’t finish performing until later.⁴

Who Can Use the Cash Method

Section 448 restricts the cash method based on entity type and revenue.

The Gross Receipts Test

For tax years beginning in 2026, the threshold is $32 million in average annual gross receipts over the prior three tax years.¹ Stay at or below that average and you can use cash regardless of whether you’re a C corporation or a partnership with a C corporation partner. Exceed it and you’re generally required to switch to accrual.⁵ The figure adjusts annually for inflation, so check the current revenue procedure before relying on last year’s number.

Entity Restrictions

Three types of entities face restrictions even below the threshold: C corporations, partnerships with a C corporation partner, and tax shelters. The first two get relief when they meet the gross receipts test. Tax shelters are barred from the cash method at any revenue level.⁵

Personal Service and Farming Carve-Outs

A C corporation working in health, law, engineering, architecture, accounting, actuarial science, performing arts, or consulting can qualify as a qualified personal service corporation and use cash accounting even when it would otherwise be restricted. Substantially all of the stock must be owned by employees performing those services, retired employees who used to, their estates, or their heirs (for two years after the employee’s death).⁵

Farming businesses have their own carve-out. Farming C corporations and farming partnerships with C corporation partners can use the cash method without meeting the gross receipts test.⁵

Inventory: The Small Business Exception

Businesses that sell merchandise were historically required to use accrual for purchases and sales so that cost of goods sold lined up against revenue.⁶ That pushed a lot of small retailers and manufacturers into accrual even at modest revenue.

The Tax Cuts and Jobs Act changed that. A business meeting the $32 million gross receipts test can now choose simplified inventory methods instead of full accrual treatment. The two main options are treating inventory as non-incidental materials and supplies (deducting costs only when the inventory is provided to customers) or conforming to whatever method appears on the business’s audited financial statements.⁶

Hybrid Methods

You aren’t locked into one pure system. The IRS permits hybrid methods that combine cash and accrual, provided the combination clearly reflects income and you apply it consistently. A common setup uses accrual for inventory-related purchases and sales and cash for everything else.²

Two constraints matter. If you use cash for reporting income, you have to use cash for reporting expenses (and the same pairing applies to accrual); you can’t mix them to maximize deductions. And any combination that includes cash is treated as the cash method for Section 448 purposes, so the gross receipts test and entity restrictions still apply.

Picking Your Method (And Switching Later)

You lock in your accounting method by filing your first federal income tax return using it.² There is no separate election form. From then on, you must use the method consistently unless the IRS approves a change.

If you qualify for cash, it’s usually simpler and gives you more control over the timing of income and deductions. Accrual gives a more accurate picture of long-term profitability, which tends to matter when you’re seeking outside investment or financing.

Filing Form 3115

Switching methods after your first return means filing Form 3115, Application for Change in Accounting Method. Starting to use a different method on next year’s return without approval is not an option.⁷

Many common changes qualify for automatic consent, meaning the IRS has pre-approved them if you follow the procedures. You file Form 3115 with your timely return for the year of change and send a signed duplicate to the IRS.⁸ Changes outside that automatic list require a private letter ruling and carry a user fee.⁹

The 481(a) Adjustment

Any switch creates a gap where income would otherwise be counted twice or not at all. A Section 481(a) adjustment closes that gap with a one-time correction. A positive adjustment (one that increases taxable income) is spread over four tax years: the year of change plus the next three. A negative adjustment is taken entirely in the year of change.¹⁰

A positive adjustment under $50,000 qualifies for a de minimis election on Form 3115 that lets you recognize the whole amount in the year of change. When the IRS forces a method change during an audit, the entire adjustment, positive or negative, is recognized in the year of change with no spreading.¹⁰

What Happens If You Use the Wrong Method

Using a method you don’t qualify for, or applying your chosen method inconsistently, gives the IRS grounds to force a change during an audit and recalculate tax for every affected year. Any resulting underpayment is subject to the accuracy-related penalty of 20% plus interest running from the original due date.¹¹

Interest can add up quickly because it compounds from the date the tax should have been paid, which may be years earlier. An involuntary change also strips out the four-year spread for a positive 481(a) adjustment, so the full correction lands in one year on top of the penalty and interest. Switching to the correct method voluntarily, before an audit surfaces the problem, avoids most of that.

1
Internal Revenue Service. Rev. Proc. 2025-32
2
Internal Revenue Service. Publication 538 – Accounting Periods and Methods
3
Office of the Law Revision Counsel. 26 USC 461 – General Rule for Taxable Year of Deduction
4
Office of the Law Revision Counsel. 26 USC 451 – General Rule for Taxable Year of Inclusion
5
Office of the Law Revision Counsel. 26 USC 448 – Limitation on Use of Cash Method of Accounting
6
Office of the Law Revision Counsel. 26 USC 471 – General Rule for Inventories
7
Internal Revenue Service. About Form 3115, Application for Change in Accounting Method
8
Internal Revenue Service. Instructions for Form 3115 – Application for Change in Accounting Method
9
Internal Revenue Service. Internal Revenue Bulletin 2026-1
10
Internal Revenue Service. IRM 4.11.6 – Changes in Accounting Methods
11
Internal Revenue Service. Accuracy-Related Penalty