Expense tracking for freelancers: what gets missed, and what the IRS lets you keep.

Most freelancers leak real money through expense tracking that is more aspirational than actual. Small software subscriptions on a personal card. The co-working drop-in paid cash because the Wi-Fi is better. The conference ticket you tell yourself you will log later, then do not. The client lunch on the wrong card, the merchant squashed to a one-line string of digits. None of these are big on any given day. Over a year they are not small at all.

The bigger problem is visibility, not just the total. Freelancers on uneven income cannot tell, week to week, what is actually spendable because business and personal outflow are tangled. The "log it later" pile never gets logged, the shoebox fills up, and by March the year is gone. What you cannot substantiate at audit the IRS treats the same as what you did not spend, and the agency gets to keep the difference.

That gap is also a tax gap. Schedule C deductions most freelancers under-claim include the simplified square-footage home-office method, self-employed health insurance premiums in full above the line, business mileage at the standard rate, half of self-employment tax, and a reasonable phone-and-internet allocation against business use. The QSEHRA, solo 401(k), and SEP-IRA trio is its own decision per year. Two things separate freelancers who actually claim these. A per-line dated ledger, not a year-end spreadsheet rebuilt from memory. A spreadsheet backed by receipts is not substantiation, and the IRS has been clear about that for a decade. And a habit of keeping business and personal spend on separate cards, or marking personal lines that way on the day they hit.

This is the work Marginmoth is built for. A nightly bank and card sweep pulls every line the day it posts, so the "log it later" pile never forms. The confidence-scored categorizer from our second post puts recurring software, AWS, co-working and travel into the right Schedule C bucket automatically, with a per-line score your bookkeeper signs off on. Ambiguous lines land in a review queue, not silently overridden. The monthly P&L from our third post maps directly to what your CPA files from, so the home-office and mileage items are already apportioned and the paperwork trail is on paper.

The piece that closes the loop is the tax-reserve projection. The SE-tax bite, the quarterly estimate, and the cash-flow hit that comes with each one surface as they accrue, not in April when the money is already gone. The deduction is only half the win. The other half is the cash you did not lose because you saw the liability coming.

Marginmoth is $79 a month, no setup fee, no per-transaction surcharge. Tools that promise purely AI bookkeeping with no human review and no per-line score fail audits at a rate their marketing copy does not mention. A close your CPA will sign off on is the bar, and that is the bar this product is built against.