Challenge 22

Find the Subscriptions You Forgot

Take a year of bank transactions and find every charge that quietly repeats each month, with what it really costs you per year.

IntermediateComplexity:Time: 30–40 min

Your task

Here is a year of bank transactions. Find every charge that repeats each month and tell me what each one costs per year, most expensive first.

Your bonus task

Example use cases

Anyone who suspects they are still paying for an app they stopped using two years ago.
A small business owner going through the company card before the accountant does.
Any search for a pattern hidden in a long list – repeat customers, recurring errors, weekly deliveries.

Before you start

01
Sign up for n8n Cloud or open your n8n workspace. No other account is needed.
02
The statement is a practice file, not real data: bank-transactions-2026.csv holds 150 transactions across all twelve months of 2026, with the columns date, merchant and amount in euros.
03
Nothing leaves n8n. The file is public, and the whole challenge runs inside your own workspace.
04
Open the file in a browser first and read a few lines, so you know what the columns look like before you build.

Nodes you'll use

What the workflow must do

01
The workflow finds exactly five merchants that were charged in all twelve months, listed most expensive first.
02
Each line says what that merchant costs for the year: FitPass Gym 388.80, NewsDaily 144.00, Streamly Music 119.88, Nimbus Hosting 90.00 and CloudBox Storage 59.88 – 802.56 euros together.
03
Merchants that only look regular never appear, including Vinyl Club, which is charged four times in the year. Bonus: FitPass Gym is flagged as having gone up from 29.90 to 34.90.

Tip

0/5

Reveal up to five tips, one at a time.

Solution

Reveal the completed workflow only when you are ready to compare it with your own.

Submit as solved

Submit when your team has a working workflow to demonstrate.