Set your records up in October and next April takes an afternoon

The reason a self employed tax return eats a weekend is rarely the form. It is the reconstruction. Someone sits down in March with fourteen months of card statements and tries to remember what a $312 charge in June was for, whether the gas was for a job or for a vacation, and where the receipt for the compressor went. The form itself takes an hour once the numbers exist. Making the numbers exist is the whole job, and October is a better month to start than March.

What follows is a system rather than a product. It works on paper, in a spreadsheet, or in accounting software, and the choice between those matters far less than the habits underneath.

Open a separate account and route everything through it

This is the single change that does the most work. One checking account and one card used only for business income and business spending. No groceries, no personal subscriptions, nothing mixed. When the accounts are clean, the statement itself becomes most of your bookkeeping, and every transaction on it is presumptively deductible rather than a question to be answered later.

You do not need a business entity to do this. A sole proprietor can open a second personal checking account and use it exclusively for the business. The test a charge has to pass, that it was ordinary and necessary for the business, is the same whether or not there is an entity behind it, and the IRS states that test in plainer language than most people expect. What separation buys you is not a different rule. It is the ability to prove which side of the rule a given charge falls on.

Decide how money leaves the business, and stick to it

Pay yourself by a single transfer on a fixed date rather than by paying personal bills out of the business account as they arrive. One transfer a month or two a month is easy to explain and easy to track. Twenty small personal charges scattered through the account is the thing that turns a clean set of records back into a mess.

Do the same on the way in. Every dollar a customer pays goes into the business account first, including cash. Cash that goes straight into your pocket is income you will forget, and forgetting income is the error that causes actual trouble rather than merely inconvenience.

Build the receipt habit around a single place

Receipts matter for two reasons: to substantiate a deduction if anyone asks, and to remind you what a charge was for when you cannot recall. Both purposes are served by one rule, which is that every receipt goes to the same place within a day.

• Photograph paper receipts and file the image in one folder named by year.
• Forward emailed receipts to one dedicated address or label them in one folder.
• For anything over a few hundred dollars, add a one line note saying what job or purpose it was for.

The note is the part people skip and later wish they had not. A photo of a receipt for lumber tells you nothing in fourteen months. A photo plus the words "deck framing, Marchetti job" answers every question anyone will ask about it.

Log the two things a statement cannot tell you

Mileage and home office use both depend on facts your bank does not know. For vehicle use, the note has to cover where you went, what the trip was for, when it happened and how far it was. Typing that into your phone before you drive off again is enough. Reconstructed mileage logs are the weakest common category of substantiation and the easiest thing to fix in advance.

For a home office, measure the room once, write down the square footage and the total square footage of the home, and keep that note. You will use the same two numbers every year until you move, and the measurement takes ten minutes now against an afternoon of guessing later.

Reconcile monthly, in twenty minutes

Once a month, open the statement, check that every line is categorized, and note anything you cannot identify while the memory is still available. Twenty minutes, twelve times, is four hours a year. The alternative is the same work compressed into a single miserable weekend, done worse, at the point in the year when you have the least room to fix anything you find.

The reconciliation also surfaces things you want to know for reasons other than tax. A subscription you stopped using in May. A supplier whose prices moved. A month where the money was fine and a month where it was not. Bookkeeping done monthly is a business report. Bookkeeping done annually is only ever a tax chore.

Start with the account separation this week. Everything else is easier once the two streams stop crossing, and by April the return will be a matter of reading numbers you already have rather than inventing them.