Finances in a Spreadsheet or an App? When the Sheet Is Enough — and When It Breaks
Key takeaways
- A spreadsheet wins as long as you keep it up — flexible, free, and the data is yours.
- It breaks in three places: being up to date, silent formula errors and completeness across many accounts.
- The effort never lies in calculating, but in gathering.
- German bank CSVs use semicolons, decimal commas and DD.MM.YYYY dates — a spreadsheet set to English often misreads them.
- Switching is not a break: CSV is the bridge, the spreadsheet stays.
Of the five app categories, the spreadsheet is the underrated one. Many people who genuinely have their finances under control keep a spreadsheet — not because they could not find an app, but because the spreadsheet does exactly what it should.
Why the spreadsheet wins for so long
Three qualities no app fully replaces:
- Flexibility. Every special case is one formula away: the annual service-charge statement, the shared-flat kitty, the side business, the property with special repayments.
- Independence. No provider, no subscription, no features being switched off.
- Ownership. The file is with you, in a format that will still be readable in twenty years.
That is a serious argument, and comparisons wave it away too often.
The three places where it breaks
1. Being up to date. A spreadsheet is always as current as your last Sunday evening. That is not a character flaw: the effort is not in the arithmetic but in gathering transactions from several accounts. That work repeats every month, and at some point it gets skipped once. After that, getting back in costs more than the monthly upkeep ever did — and that is where most spreadsheets die.
2. Silent errors. A sum formula that does not include a newly inserted row looks like a correct number. There is no cross-check and no error message. The longer the spreadsheet grows, the greater the chance that somewhere there is a number nobody recalculates any more.
3. Completeness. With every additional account the effort of entering data rises linearly — motivation does not. With two accounts it works; with five plus a portfolio it becomes a side job.
The German CSV trap
If you run your spreadsheet in English, this is the practical problem you will hit first. German banks export CSV files with semicolons as separators, commas as decimal marks, full stops as thousands separators and dates as DD.MM.YYYY. A spreadsheet set to an English locale reads “1.234,56” as text and may turn “03.04.2026” into 4 March — silently.
The fix is not to edit the file by hand but to import it with the right settings: choose the semicolon as delimiter and German as the locale for numbers and dates in the import dialog. Do it once correctly and save it as a template. More on getting the file in the first place: Export your bank statement as CSV.
What the spreadsheet does better
To be fair: in two cases the spreadsheet is clearly superior to an app.
- When your situation is unusual. Letting out property, self-employment, shared kitties, uncommon assets — standard software rarely maps special cases cleanly; a spreadsheet always does.
- When you want to calculate, not just see. Scenarios, what-ifs, your own forecasts: that is what a spreadsheet is built for.
Switching is not either-or
Switching is often understood as a decision against the spreadsheet. It is not:
- Export your transactions as CSV — from the bank, not from the spreadsheet.
- Import them into an app with an import function. From here on, it does the gathering.
- Keep the spreadsheet for what it does better — scenarios, special cases, your own logic.
The number most people built their spreadsheet for in the first place is only a subtraction anyway:
The honest counter-case
If you have kept your spreadsheet for years, it is up to date and you understand it: do not switch. A maintained spreadsheet beats any app you stop opening after two weeks.
The right moment to switch is a different one — the moment you notice you no longer keep it up. Not the moment someone tells you spreadsheets are old-fashioned.
sum takes over exactly the part where spreadsheets die: gathering. Accounts, portfolios, valuables and debt in one place, spending categorised automatically, recurring payments detected. Today your transactions come in via CSV import — the same file you would have loaded into your spreadsheet —; the automatic bank connection (PSD2) is in the works.
Frequently asked questions
Is a spreadsheet enough for my own finances?
Yes, as long as you actually keep it up. A maintained spreadsheet beats any app you do not open. The break does not come from missing features but from fading upkeep.
What can an app do that a spreadsheet cannot?
Gathering. The arithmetic is trivial in a spreadsheet; the effort lies in collecting transactions across many accounts. An app takes exactly that part off you — in return it is less flexible if you need your own special logic.
How do I move my data from the spreadsheet into an app?
Via CSV. Almost every bank exports CSV, and finance apps with an import function read it. Your existing spreadsheet stays as it is — switching is not deleting.
Is my data safer in a spreadsheet than in an app?
Not automatically. A local file is only as safe as the device and the backup behind it; an unencrypted spreadsheet in a cloud is even less so. For both, what decides is where the data lies and who can access it.
Read on
- How to keep a spending journal
- Export your bank statement as CSV
- Finance apps and privacy
- Finance apps compared
Sources
- Own analysis of the functional categories; as of September 2026. Individual products are deliberately not rated, because feature sets change constantly.
This article is for information only and does not constitute investment or tax advice.
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