You both sign the return, so you both sit in the meeting

Quick answer: Book the accountant meeting for October or November, not April. Both of you attend. Bring the questions below. Rules change every year and every state differs, so treat this as a list of things to ask, not instructions.

In most couples who run a business together, one person does the taxes and the other finds out the result in April. Sometimes it's a nice surprise. Often it's a check for several thousand dollars nobody saw coming.

That arrangement feels efficient. It's actually a risk.

Why you both go

When you file jointly, you're each responsible for the whole return. The IRS can pursue either spouse for the full amount, including errors you never knew about. Relief provisions exist for spouses who truly didn't know, but you don't want to build a marriage on the hope of qualifying.

The practical point is simpler. These decisions shape your retirement, your health coverage and what your family keeps. Both of you should hear the answers firsthand. If one of you handles the books, fine. That person still doesn't get to be the only one in the room.

If you're still sorting out who owns what in the business, run the business together, but never decide everything together is a good place to start. Taxes belong on the "decide together" side of that line.

Go in the fall

An accountant in April can only report what already happened. An accountant in October can still change it. Equipment purchases, retirement contributions, payroll for family members and timing of income all have year-end deadlines. Miss them and the conversation turns into regret.

Ask for a one-hour planning meeting, and expect to pay for it. It tends to return more than it costs.

Question one: what's our structure costing us?

Self-employment tax is 15.3 percent on net earnings: 12.4 percent for Social Security and 2.9 percent for Medicare. It sits on top of income tax. Employees pay half of it and their employers pay the other half. You pay both.

That's why many couples ask about an S corporation. In that setup you pay yourselves a reasonable salary, which carries payroll tax, and the remaining profit is taxed differently. The savings can be real once profit is high enough.

It isn't automatic, though. You take on payroll filings, a separate business return, possibly state fees, and an accountant's bill that goes up. At modest profit, the extra cost can eat the savings. And "reasonable salary" is something the IRS looks at closely.

Ask: at our profit, does a different structure save money after all the added costs? What number would make it worthwhile?

Question two: how should we be paid, and does each of us get credit?

If you're a married couple running an unincorporated business that only the two of you own, there's an option called a qualified joint venture. Each spouse reports their share on their own schedule, no partnership return required, and each spouse earns Social Security credit under their own record. Both of you generally have to take an active part in the business.

This matters more than people think. If only the husband's name carries the earnings, the wife who works beside him all day may be building no Social Security record of her own. Same goes the other way around. Ask your accountant how each of you is being credited, and whether that matches the work you actually do.

Question three: what are we doing for retirement?

Self-employed people have no employer match and no 401(k) at the office. The accounts you can set up yourselves include a SEP IRA, a SIMPLE IRA and a solo 401(k). A solo 401(k) is typically open to a business with no employees other than the owner and a spouse, and in many cases each spouse can contribute on their own record.

Contribution limits change yearly. Ask what each of you can put away this year, and whether the deadline is December 31 or the filing date.

Then ask the harder question: can we afford to do it, and what happens to our cash if we do? The best retirement plan is the one you can fund in a slow month.

Question four: what about health insurance?

Self-employed people can often deduct health insurance premiums for themselves, a spouse and children. There are conditions, including limits if either of you is eligible for coverage through another employer. If you're on a high-deductible plan, ask about a health savings account too.

Have your premiums for the year ready. Don't guess.

Question five: can our kids be on payroll?

Possibly, if the work is real and the pay is reasonable. Children under 18 working in a business owned only by their parents are generally exempt from Social Security and Medicare taxes, which is a point to confirm with your accountant. A twelve-year-old filing and sweeping for a fair wage is one thing. A paycheck for nothing is another, and the IRS knows the difference.

The full case is in put your kids on payroll before you put them in the will. Ask your accountant what to document: a job description, hours, pay records.

Question six: what can we really deduct?

Three areas go wrong most often.

• Home office. The space generally has to be used regularly and exclusively for business. The kitchen table you also eat dinner at usually doesn't qualify. A spare room with a desk and a door might.
• Vehicles. Keep a mileage log, written at the time, not rebuilt in March from memory.
• Meals and travel. Rules are narrower than most people assume. Ask for the list in writing.

If the business account and the family account are tangled together, sorting this out costs you hours at your accountant's hourly rate. Share the business, not the checking account covers how to separate them.

Question seven: how do we pay it quarterly without panic?

Self-employed couples generally owe estimated tax four times a year. Underpay and you can face penalties. Ask your accountant about the safe harbor rules, which let you base payments on last year's tax rather than guessing this year's.

Then get one number: the percentage of every deposit that goes into a separate tax savings account. Move it the day the money lands. Don't touch it for groceries, even in a rough month.

Bring these to the meeting

• Last year's return and this year's profit-and-loss statement to date
• A rough forecast for the rest of the year
• Any big purchase you're considering
• Health premiums, mileage and home office square footage
• Names and ages of any kids who work for you
• A written list of the questions above, with room for answers

Both of you take notes. Compare them in the truck on the way home.

Leave the books cleaner than you found them

Hand your accountant tidy records and the hour goes to strategy instead of archaeology. Pay your estimates on time. Return calls the same week. Good accountants remember the clients who make their job easy, and they give a little more thought to those files.

Taxes are the one bill that shows up with both your names on it. Treat the meeting like one you're attending together, because you are.