At pre-seed the job is not sophisticated accounting. It is a clean foundation that will not have to be unpicked in a year.
At a glance
Pre-seed bookkeeping is mostly an exercise in not creating problems. There is little revenue to recognise and few transactions to categorise. What there is, is a set of decisions made in the first year that either hold up under seed diligence or cost real money to fix.
If founders hold stock subject to vesting, an [83(b) election](/glossary/83b-election) must be filed within 30 days of the grant. Miss it and you are taxed as the shares vest, on the value at each vesting date, which for a company that works out is a very large bill for money you never received.
This is not like a missed filing that can be caught up with a penalty. The window closes and the election is gone. It is the single most expensive thing a pre-seed founder can forget, and it happens because at the moment it matters, nothing feels urgent.
A dedicated business bank account from the day the entity exists. Not because it is more organised, but because commingled personal and company spending is the thing that makes a later clean-up expensive — every transaction has to be re-examined by someone who was not there.
The foundation: entity and equity hygiene, a clean chart of accounts that will still make sense at Series A, monthly categorisation, and runway you can actually see. Flat pricing, and the books belong to you.