Running a small business leaves little time for paperwork, yet knowing exactly who owes you money still has to be done properly. The Debtors List Builder turns that chore into a short routine you can finish in minutes. You type in your figures, press one button, and the tool adds everything up for you. There is no account to create, no file to install, and no spreadsheet to build from scratch. Everything runs in your browser, so you can use it on a phone, a tablet, or a computer. This page explains how the tool works, what each field means, and how to read the results with confidence.
What the Debtors List Builder does. It takes each unpaid invoice, subtracts what was already paid, and groups the remaining balance by client. Instead of hunting through notebooks, bank statements, and loose receipts, you keep one tidy list in one place. Each row holds one entry, and the tool groups and totals the list for you. That single view makes it easy to spot mistakes, answer a supplier or client question, and prepare for your accountant.
How to fill in the tool. The rows use these columns: client, invoice number, invoice amount, amount paid. Start with your first entry and work down the list in order. You can add as many rows as you need with the Add a row button. If you make a typo, just correct the figure in the row and press Calculate again. Empty rows are ignored, so you do not need to delete a blank line before you calculate. Keep the wording of names consistent, for example always writing a client name the same way, so the grouped totals stay correct.
A worked example. Ana owes 500 on one invoice with 200 paid and 100 on another with nothing paid, so Ana owes 400 in total, while Bo owes nothing after paying in full. When you press Calculate, the tool shows each row result followed by the totals. Check the first two lines against your own mental arithmetic. If they match, the rest of the list is almost certainly right too. If a total looks wrong, scan the rows for a missing decimal point, a duplicated entry, or a figure typed in the wrong column. Those three slips cause most errors, and all three are quick to fix.
How to read the results. The per-client totals tell you who to chase first, starting with the largest balance and the oldest invoice. The totals are the figures that matter most for decisions, so read them first and the row detail second. A total that moves sharply from one month to the next is worth a second look, not a panic. Open the rows for that period and check whether one large entry explains the change. Small, steady changes usually reflect real trading, while sudden jumps usually point to a typo or a missing entry.
Making it part of your routine. Update the paid column the moment money arrives, so the list never overstates what clients owe. The best habit is a short weekly update rather than a large catch-up at year end. Ten minutes a week keeps the list fresh, and fresh lists are far easier to trust. Set a fixed day, for example every Friday afternoon, and enter the week entries before you close up. At month end, copy or print the result and file it with your other monthly records. That printed copy is a useful backup even if you keep the live list here.
Common mistakes to avoid. The most common mistake is mixing figures from different months or different businesses in one list. Keep one list per business and update it in date order. A second mistake is rounding every figure before typing it in, which slowly drifts the totals away from your real records. Type the exact figure from the document and let the tool do the rounding in the display. A third mistake is forgetting entries that felt too small to matter. Small entries add up, and a complete list is worth much more than a nearly complete one.
Privacy and cost. The Debtors List Builder is free to use, with no sign-up and no payment step. Your figures stay in your own browser while you use the tool. Nothing is sent to an account, and nothing is stored on our servers as part of the calculation. If you want a permanent record, use the Copy button to paste the result into your own notes, or use Print to make a paper copy.
Limits to keep in mind. This tool adds, groups, and totals the figures you enter, and it does not check them against your bank account or your tax office records. It is an estimate and planning aid, not professional financial advice. Tax rules, deadlines, and reporting duties differ by country and by business type, so check anything important with a qualified accountant or adviser. If a figure affects a tax return or a legal filing, confirm it against the original document first.
Version en espanol: Lista de Deudores por Cliente