What should I do with cash sitting in my business account?
Cash left in an operating account is doing two jobs badly: it is not earmarked for the estimates coming due, and any interest it earns is taxable. The discipline is a separate tax-reserve account funded from each month's profit, sized to the year's projected liability, so an estimated payment is never a cash event. Where cash beyond reserves should go is a question for a licensed investment adviser.
Key points
- Cash pooled in a single operating account is not earmarked for estimated taxes, and any interest it earns is itself taxable income.
- A separate tax-reserve account funded from each month's profit turns a quarterly estimated payment into a routine transfer rather than a cash event.
- The tax reserve is sized to a projected annual liability that is updated at least once or twice during the year.
- Surplus cash beyond the tax reserve and the operating cushion loses purchasing power to inflation if it sits idle indefinitely.
- Where surplus cash should be invested is investment advice that belongs to a licensed investment adviser, not a tax professional.
Why is cash sitting in the operating account a problem?
Cash pooled in a single operating account feels like a sign of health, and up to a point it is. But an undifferentiated balance is doing two jobs badly at once. It is not clearly earmarked for the taxes that are coming, so the money that belongs to the government feels like money that belongs to the owner and gets spent. And any interest it earns is itself taxable, reported on the return as ordinary income, so even the small return it generates adds to the liability it is failing to prepare for.
The result is predictable: the quarterly estimated payment arrives as a surprise, the operating account is drained to meet it, and the business spends the next month recovering. Underpaying the estimate instead triggers the underpayment penalty under section 6654, which is computed like interest on the shortfall.
How do you set up and size a tax reserve?
The discipline that fixes the problem is separation. Open a distinct tax-reserve account and fund it from each month's profit, moving a set portion the moment the profit is booked rather than at the end of the year. Size the running total to the year's projected liability, which comes from a real projection rather than a guess, and revise it as the year develops. When an estimated payment falls due, transfer from a reserve built for exactly this purpose, and the payment stops disrupting operations. The same principle applies to any large known future outlay, such as an annual insurance premium or a bonus commitment.
Doing this well depends on knowing the number, which is why the tax reserve and a mid-year projection go together. Without a projection the business is either under-reserving and facing a shortfall, or over-reserving and starving itself of cash it could use. A projection updated at least once or twice through the year keeps the reserve accurate in both directions, and the safe-harbour rules for estimated payments give a floor to plan around.
What can a tax professional say about surplus cash?
Once the tax reserve is funded and the operating cushion is set at the months of expenses the business needs, what remains is genuinely surplus cash. A tax professional can describe the shape of that decision. Surplus cash sitting idle in a low-return account loses purchasing power to inflation over time, so leaving it there indefinitely is itself a choice with a cost.
Common directions for surplus include reinvesting in the business, funding retirement plans that also carry a deduction, and paying down debt, which removes an interest cost the business is already paying. Which of those, and in what order, depends on the owner's rates, goals, and advice from the right professional.
What is outside a tax professional's scope?
Deciding where surplus should be invested, meaning into what kind of account, instrument, or holding and at what balance of return and liquidity, is investment advice. It is the province of a licensed investment adviser who can look at the owner's full picture and tolerance for fluctuation. It is not something a tax professional should answer by naming products, banks, or expected yields, and this page does not.
The tax-side job is narrower and clear: reserve for what is owed, hold what the business needs to operate, and do not let the rest sit unexamined. A reserve also cannot fix a liability that was never projected, so a business that has not run a mid-year projection should start there before it moves any cash.
Related strategies
People also ask
- How much cash should my business keep?
- How do I pay quarterly estimated taxes?
- How do estimated taxes and the safe harbour work?
- How do I make money work for me in the US?
Sources
Related guides: cfo
Mena Hemaia, CPA, CIA
Chief Executive Officer, Accountack — West Palm Beach, Florida
If you want to know which of these apply to your business specifically, that is a conversation about your actual numbers — not a seminar example.
Or start with the Free Cash Clarity Audit — A no-cost review of where your business stands and what a planning engagement would target — the firm's own named starting point.
20 minutes with an Accountack advisor. If a technical review is worth your time, the next step is a workshop with Mena — and if there is nothing material to do, he will say so.