Can I afford it?
Type an amount and the verdict updates as you type. Yes, no, or the one Plumb is most useful for — yes, but it breaks the plan, with what it would cost your budget and your per-day figure for the rest of the cycle.
Know what's left to spend.
Plumb is a budget app for iPhone. You log what you spend, and it tells you what is actually free — after the cards, the bills, and the money you have promised to your goals.
Plumb keeps your ledger on the device. In its own words, on the first screen you ever see: nothing leaves your phone, no credentials, ever.
How it works
One question, answered honestly.
Most budget apps show you what you have spent. Plumb is built around the question you actually ask in the shop — and it will tell you no.
A cycle that starts on payday
Your budget runs from the day of the month you are actually paid, not from the 1st. A start day past the end of a short month lands on its last day, so February does not quietly break the plan.
Balance checks that catch the drift
Every ledger drifts. Plumb tells you what it recorded, you type what your bank shows, and it files the difference as a real entry you can categorise — not a silent correction.
Goals the budget respects
An emergency fund, or the trip you keep putting off. Fund a goal by hand or on a schedule — either way the money you have promised it stops counting as money you can spend.
Everyday accounts in one ledger
Checking, savings, cash, credit cards and investments. Plumb knows which of them you can actually spend from, so a healthy investment balance never flatters the figure at the top of the screen.
Insights, once you have logged enough
Where the cycle went, by category, and how it compares with the one before. When there is not enough history to say anything true, Plumb says that instead of drawing a chart.
Privacy
There is no server to leak.
Plumb has no backend. Your accounts, transactions, budgets and goals are written to a database on your iPhone and never sent anywhere. This is not a policy we could change next quarter — there is nothing in the app that could send them.
- No account to create and no password to choose. You open the app and start.
- No bank credentials, ever. Plumb never asks for a login to anything.
- Lock the app behind Face ID, Touch ID or your passcode.
- Hide every figure on screen with one setting, without touching your data.
- Delete everything from the device whenever you want, and start over.
Before you decide
What Plumb does not do.
Worth knowing before you start, because these are choices rather than gaps.
- It does not connect to your bank. You type what you spend. That is the cost of the paragraph above, and it is the whole reason the app can make that promise.
- It does not sync between devices. The ledger lives on one iPhone.
- It does not guess. Nothing is auto-categorised, and no charge is flagged as a subscription unless you flag it.
- It is an iPhone app. There is no iPad, Mac, Android or web version.