About BillMapper

BillMapper makes free planners for the bills that don’t come monthly — and runs every one of them in your browser, so your numbers never leave your device.

Why this exists

We kept watching the same thing happen — to ourselves and to everyone we knew. People who were perfectly careful with their monthly budget would still get knocked sideways twice a year, when a clump of big irregular bills landed in the same few weeks. Insurance, property tax, registration, the December gift spike: none of them is a secret, but spread across a year and out of sight, they may as well be. We wanted a single tool that pulls them all onto one calendar so the heavy months stop being an ambush.

How we build our planners

• Show the method. Every tool explains exactly what it’s doing — how it spreads a bill across the year, how it finds your worst month, and how it works out the monthly set-aside. No black boxes; you can check it with a calculator.
• Run everything in your browser. The planners are 100% client-side. The incomes, bills and amounts you type are never uploaded, logged or sold. Anything you save lives in your own browser’s storage, and you can clear it in one click.
• Make the output yours. A plan you can’t keep isn’t much use, so our tools export — a printable one-page calendar, a file you can drop into your own phone calendar.
• Stay in our lane. We do cash-flow planning and estimates. We are not financial advisers, and we say so plainly rather than pretending a calculator can replace one.

Who’s behind it

BillMapper is built and maintained by a small independent team (we publish under the brand name rather than personal names). We don’t sell insurance, loans or financial products, which means we have no reason to nudge you toward anything — the only job of a tool here is to show you your own year clearly. If a planner gives a strange answer or a guide gets something wrong, we want to know: get in touch.

How we keep it free

The site costs very little to run, and the plan is to cover that with unobtrusive advertising and, in time, affiliate links to tools we’d actually use ourselves. None of that changes what a planner tells you. The details are on our Ad & Affiliate Disclosure page.