How much can I spend until payday?

The quickest way to stop running short before payday is to turn “what's in my account” into a daily amount. It takes three numbers and a date.

The sum

1. Start with the money in your account now.
2. Take off every bill still due to leave before your next payday: rent, phone, subscriptions, card payments.
3. Take off anything you plan to move to savings before payday.
4. Divide what's left by the number of days until your pay arrives.

For example (fictional figures): £640 in the account, £310 of bills still to go and £100 to savings leaves £230. With 11 days to payday, that's about £20.90 a day, or about £146 a week.

Things that catch people out

• Payday moves. If your payday falls on a weekend or bank holiday, most employers pay on the working day before. That gives you an extra day or two this month, but the next gap is longer.
• Annual bills. Car insurance, TV licence or a yearly subscription can land in a month you weren't expecting. Check last year's statements for anything that renews.
• Pending card payments. Some apps show your balance before recent card payments have gone through. Take those off too.
• Christmas pay. Being paid early in December can leave a much longer wait for January's pay. See the long January pay gap.

Keeping it up to date

A daily amount only helps if it changes when you spend. If you go over one day, the amount for the remaining days goes down a little. If you spend less, it goes up. Re-run the sum every few days, or let an app do it for you.