Year-End Tax Planning Checklist for South Carolina Business Owners

Almost everything that reduces a tax bill has to happen before the year ends. Once the calendar turns, preparation can only record what already occurred — the decisions that moved the number were made months earlier, or were not made at all.

This is the review worth doing in the final quarter, while there is still time to act on what it finds.

Every item below depends on knowing roughly where the year will land. That requires books that are current — not perfect, but current enough to project the year with confidence.

If the books are months behind, that is the first job, and it is genuinely urgent rather than administratively annoying. Planning against a guess is not planning.

A business on cash basis accounting has real latitude over which year income and expenses fall into, within the bounds of ordinary business practice.

The direction depends on which year you expect to be the higher-income one. Deferring income into a year when you will be in a higher bracket is a loss, not a saving — the point is to move income toward the lower-taxed year, not simply to delay it.

Assets bought and placed in service before year end may be deductible in that year rather than over time, depending on the asset and the provisions available. "Placed in service" is the operative phrase — ordering equipment in December that arrives in February does not create a current-year deduction.

The caution worth stating plainly: buying something you do not need to reduce tax is a poor trade. You spend the whole amount to save a fraction of it. Accelerate purchases you were going to make anyway; do not invent purchases.

This is the most underused lever available to profitable small businesses. Employer retirement plans allow contributions well above individual limits, they reduce current taxable income, and the money remains yours rather than leaving the business.

Timing rules differ by plan type — some plans must be established before year end even if funded later, others allow both later. Establishing the plan is frequently the deadline that bites, so this is a question to ask in the autumn, not in March.

If the business has grown materially, the structure chosen at the start may no longer fit. The S-Corp question in particular is worth revisiting annually, because the threshold at which it starts making sense is crossed silently.

Elections have their own deadlines, generally well before the return is due, so a structure change identified in April is usually a change for the following year rather than the one being filed.

For S-Corp owners, reasonable salary needs to have actually been paid through payroll during the year. Discovering in February that too little was run through payroll is difficult to fix retroactively, and it is one of the most commonly examined areas for small S-Corps.

Also worth confirming before year end: bonuses intended for this year are processed, contractor payment records are complete enough to issue year-end forms, and any owner draws are recorded properly rather than left as unexplained withdrawals.

The final estimate is the last opportunity to avoid an underpayment penalty, and it is the one most often paid on autopilot at a figure set in January against assumptions that no longer hold.