The Lazy Saver100 envelope challenge (UK): save £5,050
Updated 14 October 2026 · 4-minute read · UK
Number 100 envelopes from £1 to £100. Each week, pick two at random and put that amount in. After 50 weeks you've saved £5,050.
Is £5,050 realistic?
It averages about £101 a week, which is a lot for many budgets. Pick a version you can finish: half-size (50p steps, £2,525), or one envelope a week over 100 weeks.
The lazy version
Skip the 100 paper envelopes. Use a printable tracker: colour in a number when you've moved that amount into a savings pot. Same fun, money stays safe and can earn interest.
A 6-page printable with a payday bill calendar, subscription hit-list and a 30-day challenge. Free by email.
Get the free plannerTips to stay on track
Draw your envelopes on payday weekend, when money's in. Do the big numbers when you get a bonus or a refund. And if a week is tight, pick two small ones. That's the beauty of random.
Our 20-second UK calculator adds up takeaways, unused subscriptions and not switching. The yearly total is usually a shock.
Try the calculator →Savings Challenge Pack (£3.99): 8 printable challenges and a cash stuffing kit. Built for UK paydays and the 2026/27 tax year. Instant download.
See it in the shop →FAQ
How long does the 100 envelope challenge take?
50 weeks if you do two envelopes a week. You can also do one a week over 100 weeks.
How much is the 100 envelope challenge in pounds?
£5,050 at £1 steps.
Do I need real envelopes?
No. A printable tracker and a savings pot work just as well, and keep your money safer.