Almost every startup makes the same five accounting mistakes, and almost none of them is serious at first. The trouble comes with the first funding round: an investor asks for the accounts, the cap table or the months of cash left, and there is no clear answer. Here are the five, why they happen and how to avoid them without spending more than a few hours a month.
Mixing personal and company finances
What happens. You pay for the company’s software with your own card, or for a personal dinner with the company’s. By the end of the year nobody remembers which was which.
Why it happens. At the start, you are the company. It is the quickest option and it seems harmless.
How to avoid it. One account and one card just for the company, from day one. If you pay for something for the company with your own money, keep the receipt and reimburse yourself with an expense claim. If it is the other way round, it is recorded as a debt you owe the company.
Leaving the accounts until the end of the year
What happens. In December there are twelve months of unreconciled bank statements, missing invoices and expenses nobody can explain.
Why it happens. The product always seems more urgent. And the accounts never warn you when they fall behind.
How to avoid it. One hour a month, always on the same day: upload invoices, check the bank and clear up any questions. If we handle it for you, we write to you before every closing with what we need.
Keeping the cap table in a spreadsheet nobody updates
What happens. The cap table, the record of who holds how many shares, lives in a spreadsheet that is two capital increases out of date. The team’s options are buried in an email.
Why it happens. Every transaction is done in a hurry and the record is left for later.
How to avoid it. Update it at the time of each transaction: capital increase, convertible loan, options. And check that it matches the commercial register and the signed documents. A clear cap table is the best introduction you can make in a funding round.
Not setting money aside for taxes and social contributions
What happens. The tax bill for the year arrives, or the AHV adjustment, and no money has been put aside.
Why it happens. Taxes are paid months after the money is earned. In the meantime, that money looks available.
How to avoid it. Set aside part of your income each month for taxes and contributions. As a guide, AHV, disability and loss of earnings contributions currently add up to 10.6% of salary, half of it paid by the company. On top of that come other insurance and, if there is a profit, taxes. We give you the exact figure for your case.
Not keeping an eye on cash
What happens. You know how much is in the bank, but not how many months you have left. The round is delayed by three months and the account cannot hold out.
Why it happens. The bank balance is easy to check. Working out your months of cash (runway: available cash divided by net monthly spend) means having up-to-date figures. Late bookkeeping, again.
How to avoid it. Check three figures every month: available cash, net spend for the month and months remaining. Start preparing the next round when you have 9 to 12 months left, not 3.
Your five-point checklist
- A separate account and card for the company.
- One hour of bookkeeping a month, always on the same day.
- A cap table updated with every transaction.
- A monthly provision for taxes and contributions.
- Months of cash calculated every month.
If you would like to go through the five points for your own case, our startup advisory does it with you: cap table, valuation and preparing your next round.
Figures checked against official sources on 26 October 2026. They change every year, so confirm them before you act.