How to track your spending: a simple 30-day method
By Rafael · Updated · 2 min read
The short answer
Write down every purchase for one full month, the same day you make it, in about eight categories. Review the total once a week, and at the end of the month split it into fixed and flexible costs. That one month shows where your money really goes and the one change most worth making.
Why a full month
A week or two misses the bills that come once a month, like rent, insurance and subscriptions. The US Consumer Financial Protection Bureau's spending tracker suggests tracking a full month so you see income and expenses in one place, and noting the costs that are the same every month as your fixed obligations.
You don't need to link a bank account or install anything. The habit of writing it down is what makes you notice.
The 30-day method
- Pick one placePaper, a notes app, a spreadsheet or a free tracker like Spendwise. One place, so nothing gets lost.
- Log it the same dayAmount, what it was, and a category. Same-day logging takes seconds; reconstructing a week from memory doesn't work.
- Keep categories fewAbout eight is plenty: housing, bills, groceries, eating out, transport, health, fun and other. Too many categories and you'll stop.
- Mark fixed or flexibleFixed costs are the same every month (rent, loan payments). Flexible costs are the ones you choose day to day (eating out, shopping).
- Review weeklyTen minutes, once a week: total so far, the biggest category and anything that surprised you.
- Pick one changeAt the end of the month, choose one flexible category to adjust. One change you keep beats five you abandon.
Spending log: [month]
Date | What | Category | Amount | Fixed or flexible
-----|------|----------|--------|------------------
| | | |
Categories (keep it to about eight):
Housing · Bills & utilities · Groceries · Eating out · Transport · Health · Fun · Other
End of week: total so far ______ Biggest surprise: ______
End of month: total ______ Fixed ______ Flexible ______
One change for next month: ______Find the charges that repeat
Recurring charges are easy to forget because they happen without you doing anything. When the month is done, look for:
- Subscriptions you no longer use (streaming, apps, memberships)
- Free trials that turned into paid plans
- Annual renewals coming up in the next few months
- Bank or card fees you could avoid
Spendwise flags what repeats every month and shows your pace against last month, with no account. Your data stays in your browser unless you choose to save it.
What to do with what you learn
Your month of tracking is the starting point for a budget: you now know your real fixed costs and what your flexible spending usually is. If your income changes month to month, see how to budget with irregular income.
Common questions
- Do I need to link my bank account?
- No. Writing purchases down by hand (or in a simple app) for a month works well, and many people find it makes them more aware of spending than automatic imports.
- How long should I track my spending?
- At least one full month, so monthly bills are included. Many people keep going because the weekly review becomes a quick habit.
- What categories should I use?
- Start with about eight: housing, bills and utilities, groceries, eating out, transport, health, fun and other. Split a category only if it gets too big to understand.
- What if I forget to log something?
- Add it when you remember, or check your bank statement at the weekly review. Close enough is fine; the goal is a clear picture, not perfect accounting.