More than half of people say they spend more money during British Summer Time than during the winter, paying £154 on average more each month.
With the clocks having gone an hour forward earlier this week, the lighter evenings could tempt more people (57%) into loosening their purse strings, a survey from credit report provider Noddle found.
Feeling that there was more to do during the summer, meeting up with friends and family and generally feeling happier as the weather warmed up were all factors which people said would encourage them to spend more, the survey of over 1,300 people found.
Jacqueline Dewey, managing director at Noddle.co.uk said: "It's important to keep a close eye on your bank balance and not slip into relying on credit to bridge the gap between paydays over the next few months.
"Make a budget now to see you through the summer, accounting for the extra spend.
"Using your credit card a small amount each month is healthy for your credit score, but if you start to overspend or miss payments, this can have a detrimental effect on your score, making it harder to get credit when you need it for larger items like a mortgage or car."
Noddle suggested people should plan ahead to save cash over the summer, for example by making lunch at home, cutting down on takeaway coffees or walking instead of using public transport. The savings could then be put towards summer trips out and holidays.
It suggested people could also consider saving before they spend, by setting up a monthly direct debit into a savings account for just after they get paid, so they are not tempted to spend all their wages.