As we move into autumn, a burst of sunshine feels all the more special. And far from just lifting your spirits, it could now help you save money too.
You heard that right! A popular smart money app has launched a quirky new feature that allows users to save money whenever the sun comes out.
Plum, which you can download on App Store and Google Play, is famous for using automation to help people save money without even thinking about it.
Once you connect the app to your bank account, it sets aside money based on what automated savings rules, known as Auto Savers, you have selected.
The newest, Sunny Day Rule, banks money every time it’s sunny in your local area. (Plum is not a bank).

A popular smart money app has launched a quirky new feature that allows users to save money whenever the sun comes out
It’s inspired by one of Plum’s other Auto Savers, Rainy Days, which does the same any time it rains.
You can vary the amount you save by selecting one of five modes –
- Shady Spot – Saves £1
- Sunny Side Up – Saves £2
- Summer’s Here – Saves £5
- Beach Day – Saves £10
- Blazing Hot – Saves £20
Plum has crunched the numbers and found that users who turn on the ‘Summer’s Here mode could save around £519 in a year, based on the 103 sunny days we saw in 2024.
This surges to an impressive £2,076 for the highest savings mode, Blazing Hot*.
Think of it as bottling sunshine to spend later!
The Sunny Day Rule and Rainy Days aren’t the only Auto Savers Plum offers.

Plum is famous for using automation to help people save money without even thinking about it
The default mode, Automatic, uses an algorithm to scan your earning and spending patterns to work out what you can afford to spare each week, before setting it aside for you.
Another, Naughty Rule, sets aside a specific amount every time someone shops at retailers you consider a guilty pleasure, and Round Ups, which rounds up everything you spend to the nearest pound and saves the difference.
Fancy a bit of fun? Then try the 1p challenge, which sets aside a penny more every day to help people save up to £667 per year.
The idea behind Auto Savers is to automate the process of saving, so users don’t have to actively remember to set aside money themselves.
This has proven very effective in helping people build a regular savings habit, with one Plum user previously revealing how they’d used the app to save £7,000 and start investing in the stock market for the first time (capital at risk).
Graphic designer and illustrator Lily Devins found the Auto Savers so effective that she hardly noticed the money leaving her bank account.
Some Smart Saving Rules are paid features, and therefore fees apply.

Graphic designer and illustrator Lily Devins found the Auto Savers so effective that she hardly noticed the money leaving her bank account
‘I’ve chosen Payday, which sends an allotted amount that goes out each time I get paid,’ she said.
‘I’m also doing the 52-week challenge, which saves £1 in the first week of the year before increasing this by £1 each time until you get to £1,378 by the end.’
Nivedhitha Selvam, Senior Product Manager at smart money app Plum, reckons fun tricks like the Sunny Day Rule are just the ticket for making your finances less gloomy.
‘Our new Sunny Day Rule is brilliant for people who feel like they’re behind on saving and want to make their finances brighter!’ she says.
‘Over the course of a few months, you’d be shocked at just how much you can save by setting a little money aside, but frequently thanks to this new automation.’
*Calculations are made based on the 2024 number of sunny hours. Statistics taken from Statista show that last year the UK had 1,274 hours of sunshine. 1,274 / 12 hours of sun per day = 103 whole days of sunshine.
Capital at risk if you choose to invest in a General Investment Account (GIA), Stocks & Shares ISA or Self-Invested Personal Pension (SIPP). Tax treatment will depend on your personal circumstances, and these rules could change.
95 Day Notice Pocket is a savings account provided by Investec Bank Plc. You should consider whether a Pocket that delays withdrawals for 95 days is right for you.