I recently lent out a sum of money £23,000 which was agreed on a standard 5% interest repayment. There was a 6 month gap, then changing monthly sums paid back. The capital has now been repaid and I'm trying to calculate the interest

Any tips ?

Use your rows for each month, and have a column for outstanding debt, and a column for amount paid. Enter data for amount paid each month, your formula for each month past the first is (Amount_owed_last_month - Amount_paid_last_month)*1.05.

Does this help?

I made a quick spreadsheet for you if you want it just ask, I can't put it up from here but I can do so from home.

Thank you for your assistance Capuchin. Just to clarify the 5% interest is per annum , not per month

Okay how would you like to apply the interest? Monthly or weekly or something?

For monthly you need to apply 1.05^1/12 per month, which comes out to 1.00408 per month (rounded up).

Thinking about it , it needs to be daily...

Okay so that's 1.05^1/365 per day, which comes out to ~ 1.0001337 per day (rounding up)

Are you okay constructing the spreadsheet? Or I can attach my version later on today