Cash or Accrual: The Decision New Owners Make Without Realizing It

A retainer that doesn't show up for 45 days

Picture a small bookkeeping practice with eight retainer clients, each paying $1,500 a month for ongoing books and reporting. The owner sends invoices on the first of the month. Clients pay, on average, 45 days later. In March, the business does the work for eight clients: $12,000 worth of service delivered. But the cash that actually lands in the checking account in March is from January's invoices, because that's what's finally clearing.

If the owner looks at the bank balance and calls that March's income, they're using cash-basis accounting without having decided to. It's the default most new owners fall into, because it matches the number on the bank app. The problem is that it can make a business look broke in a month it was actually profitable, or flush in a month it wasn't, depending on when checks happen to clear.

The mechanical difference

Cash-basis accounting records income when money is received and expenses when money is paid out. It's simple, and for a one-person operation with no inventory and no lag between work and payment, it's often a reasonable way to run the books.

Accrual-basis accounting records income when it's earned, regardless of when the client pays, and expenses when they're incurred, regardless of when the bill gets settled. In the bookkeeping practice example, March's revenue under accrual is the full $12,000, because that's the value of work actually performed that month. The $12,000 still sitting in accounts receivable shows up as an asset on the balance sheet, not as income yet collected, but it's counted as earned.

The difference isn't just timing trivia. It changes what the numbers tell the owner. Under cash basis, a growing, healthy, increasingly busy practice can appear to be losing money in any month where collections happen to lag behind the work. Under accrual, the owner can actually see whether the retainer pricing covers the cost of delivering the work, independent of when clients get around to paying.

This is the same mechanism behind a business that looks solvent on paper while the bank account tells a different story, just running in reverse. A contractor with a full order book can still run out of cash while waiting on payment, as covered in why a full order book can still mean an empty bank account. Cash versus accrual is the accounting language for that same gap between work done and money in hand, just applied to how the books get kept rather than how the bills get paid.

When the IRS makes the choice for you

For most very small businesses, the IRS lets the owner choose either method, and plenty of sole proprietors and small S-corps use cash basis for years without issue. But the choice isn't unlimited forever. Businesses that carry inventory for sale to customers generally have to account for that inventory using accrual rules for purchases and sales, even if they use cash basis elsewhere. And once a business crosses the IRS's inflation-adjusted average annual gross receipts threshold, accrual accounting becomes mandatory for certain corporations and partnerships with corporate partners, under the rules in IRS Publication 538, which lays out which businesses fall under this requirement and how the gross receipts test is calculated.

Most owner-operators in their first few years, running a service business with no inventory and modest revenue, won't hit that threshold immediately. But it's worth knowing the rule exists, rather than discovering it the year a tax preparer flags it.

When switching makes sense before the IRS forces it

Even below the mandatory threshold, plenty of growing businesses switch to accrual voluntarily, usually around the point where the gap between work performed and cash collected gets big enough to distort decision-making. A consulting practice billing monthly retainers with a 30 to 60 day collection lag is a textbook case: by the time revenue reaches a level where a few slow-paying clients can swing a month's numbers from apparently profitable to apparently underwater, cash-basis reporting is actively working against the owner's ability to read the business.

A practical signal: if the owner regularly has to explain to themselves (or a lender, or a partner) why the bank balance doesn't match how busy the business has been, that's usually the moment accrual becomes more useful than cash. Switching isn't just flipping a setting in bookkeeping software, though. Changing accounting methods for tax purposes generally requires the IRS's consent, filed on Form 3115, which is a reason to loop in a tax preparer before making the change rather than after.

What to ask before the first return gets filed

A new owner sitting down with a tax preparer for the first business return should ask directly: which method are we using, cash or accrual, and why does it fit this business specifically? Worth also asking whether that choice is likely to still make sense once revenue grows, whether the business carries any inventory that changes the rules, and what the threshold looks like for when accrual might become mandatory rather than optional.

Those questions matter for the same reason job costing matters once a business outgrows a notebook, discussed in when job costing stops fitting in a notebook: the accounting method isn't paperwork for its own sake, it's the lens the owner reads their own business through. An owner who can say which method they're using and why is an owner who can trust what their numbers are telling them, instead of being surprised by a bank balance that never quite matches how the business actually feels.