What tracking a loan properly actually costs you

You will find articles claiming precise figures for how long people spend maintaining financial spreadsheets. One number in particular — around three hours a month — circulates widely, attributed to a survey that, as far as I can tell, does not exist. I went looking for it and found only content farms citing each other.

So I am not going to give you a number. What follows is the honest version.

The hours are not the cost

Building a loan spreadsheet takes maybe twenty minutes. Updating it takes two. If that were the whole cost, nobody would ever have a problem.

The actual cost lives elsewhere.

Remembering. Interest accrues every day. Your spreadsheet updates when you think of it. The gap between those two facts is where every wrong number comes from.

Doubting. This one is rarely named and matters most. When you open the file, are you confident the last figure is right? If there is any hesitation, you will not use it to have a conversation — and a record you do not trust enough to cite is not doing its job.

Deciding the same thing twice. Every partial repayment poses the same question: interest first, or principal? Answer it inconsistently across a year and the sheet is quietly wrong in a way no formula check will catch.

The ones you gave up on. This is the largest and least visible cost. The first loan got a careful spreadsheet. The second got a row appended to it. The third is a WhatsApp message you would have to scroll to find. At that point you do not have a system.

What is actually documented

There is no good research on time spent tracking informal loans. There is solid research on spreadsheet reliability: Ray Panko's field audits at the University of Hawaii found error rates of 84–91% across sets of operational spreadsheets — meaning most contained at least one error, not that most cells were wrong.

The relevant part is his note that human inspection catches only about 60% of errors that are present. The problem is not that spreadsheets are hard to fix. It is that you cannot tell when one needs fixing.

What changes

The honest claim is not "save three hours a month." It is narrower and, I think, more useful:

You stop maintaining anything. Interest accrues daily on its own. The balance today is correct because it was correct yesterday, not because you updated it.

You stop deciding. How repayments split follows from the loan's configuration, applied identically every time — and the split is shown on every movement.

You stop doubting. When something looks off, the history is there day by day and you can go to the exact date instead of re-deriving the whole thing.

You stop having two versions. The other person sees the same record, so a disagreement about the number becomes a disagreement you can settle by looking.

Whether that adds up to three hours a month, I genuinely do not know. What it removes is the friction that makes people stop keeping records at all — and that is the failure that actually costs money.