List invoices, bills and recurring payments once. See which week your balance dips below your buffer, a quarter ahead. Free to download.

List each invoice, bill and recurring payment once, with its date. The forecast puts every amount in the week the cash really moves and shows the first week your balance dips below your safety buffer.

Who it’s for

Small-business owners, freelancers and small teams who get paid by invoice and want to see a quarter ahead without typing numbers into week columns or shifting the grid every Monday.

What it does

• Recurring items: weekly, every 2 weeks, every 4 weeks, monthly, every 2 months, quarterly, twice a year, yearly or once, with optional end dates. Monthly dates keep their day and handle month-end (31st, Feb 29) without drifting
• Receivables: expected date = invoice date + terms + that customer's usual days late, or the date they promised
• Customers sheet: typical days late per customer (negative = pays early), with a default for everyone else
• Payables: due date or your planned pay date; put a disputed bill on hold
• Open amounts after part-payments; overdue open items counted in Week 1 (or left out, your choice)
• Doubtful invoices and bills on hold are left out on purpose, and the summary shows how much
• Forecast: 13 weekly columns by category, opening and closing balances, lowest balance and its week, first week below your buffer and below zero, plus a chart
• Stress test: add days late to every open invoice and set the share you expect to collect
• Rolls forward by changing one date and the bank balance. Check flags explain any row that isn't counted

What you get

1. 13-Week-Cash-Flow-Forecast.xlsx: the working spreadsheet (7 tabs, with a fictional example business)
2. Blank-13-Week-Cash-Flow-Forecast.xlsx: the same file with no rows filled in, ready for your own numbers
3. 13-Week-Cash-Flow-Forecast-Guide.pdf: a 4-page guide to setup, the weekly routine, how each date is placed, and every status word

Good to know

• Free instant download, no sign-up.
• A planning tool, not accounting, tax or financial advice.
• No bank feeds or imports. Weekends and bank holidays aren't shifted.
• License: free for personal or business use; don't resell or re-host. Sharing a link to the Tidewick page is fine.

Compatibility

Tested in LibreOffice Calc (free for Windows, Mac and Linux). Every calculated cell was recalculated there and checked against an independent model across 36 test workbooks, including month-end and leap-day dates, overdue and after-window items, messy data and a full 300-invoice, 300-bill file.

Other apps: not yet tested. It's built as a standard .xlsx with no macros and uses only long-standing functions (IF, INDEX, MATCH, COUNTIF/COUNTIFS, SUMIFS, EDATE, WEEKDAY, MOD, INT, ROUND, TODAY and similar). That's a good sign, but it isn't a test, so we don't claim it works in Excel, Google Sheets or Numbers yet.

Known limits. 60 recurring items, 40 customers, 300 invoices and 300 bills. One currency. Weekends and holidays aren't shifted. No bank feeds. Not accounting or financial advice. Phones and tablets haven't been tested.

How to use it

1. Download the example .xlsx (or the blank one) and the PDF guide from the product page on the Tidewick site.
2. Open the .xlsx in LibreOffice Calc (free), where it has been tested. Other apps haven't been tested yet.
3. On Settings, type the date Week 1 starts (or leave it blank for the Monday of this week), your bank balance and your minimum cash buffer. Rename the categories if you like.
4. On Recurring, add payroll, rent, loan payments, retainers and other repeating items with a frequency and first date.
5. On Customers, enter how many days late each customer usually pays. On Receivables and Payables, add your open invoices and bills.
6. Read the Forecast sheet. Each week, change the Week 1 date and bank balance, and update what was received or paid.

Questions

Do I need Excel?

No. It has been tested in LibreOffice Calc, which is free. It's a standard .xlsx with no macros, but it hasn't been tested in Excel, Google Sheets or Numbers yet.

How do I roll it forward each week?

Change the Week 1 date on Settings to the new Monday and type your new bank balance. Then fill in Received so far / Paid so far. Nothing needs to be moved by hand.

What happens to an invoice that's overdue?

If it's still open, it's counted in Week 1 and marked "Overdue → Week 1". You can switch that off on Settings, or mark it Doubtful to leave it out.

How are monthly dates on the 31st handled?

They fall on the last day of shorter months (Feb 28, Apr 30) and go back to the 31st in months that have one.

What does the stress test do?

It adds extra days to every open invoice's expected date and/or counts only a share of each invoice (for example 80%), so you can see whether you still stay above your buffer.

How big can it get?

60 recurring items, 40 customers, 300 invoices and 300 bills, with 8 money-in and 12 money-out categories.

Is this financial advice?

No. It's a planning tool. The example business and amounts are fictional.

Does it cost anything?

No. It's a free download with no sign-up.