The 13-Week Cash Forecast: A Simple Template for Small Businesses

Most small businesses don't run out of profit. They run out of cash. A month can look great on the profit and loss statement while the bank balance quietly drops toward payroll day. A 13-week cash forecast is one of the simplest tools for seeing that coming.

This guide walks through what a 13-week cash forecast is, how to build one in a spreadsheet, and how to use it every week without it becoming a second job. It's written for owner-operated businesses in Kalamazoo, Portage, and anywhere else.

What a 13-week cash forecast is

A 13-week cash forecast is a week-by-week projection of the cash coming into and going out of your business over the next quarter. Thirteen weeks is long enough to see quarterly bills and seasonal swings, and short enough that your guesses are still reasonably good.

It's different from a budget. A budget asks, "How profitable will we be this year?" A cash forecast asks, "Will there be enough money in the bank every week to pay what's due?" Those can have very different answers, because profit is not cash. Customers pay late, inventory gets bought before it sells, loan payments and owner draws don't show up as expenses, and tax payments land in lumps.

If you want a quick first read before building anything, try our cash runway checker. It estimates how many months your current cash covers based on typical money in and out. The 13-week forecast is the more detailed, week-by-week version of the same idea.

The template: five sections

Set up a spreadsheet with 13 columns, one for each week, starting with the current week. Use the week's start date as the column heading. Then add these rows.

1. Beginning cash

For week one, this is your actual combined balance in your operating bank accounts today. For every later week, it's the prior week's ending cash. Don't include money you can't actually spend, like funds held for customers or a reserve you've committed to leave alone.

2. Cash in

List the money you expect to receive, by week:

• Customer payments on open invoices. Use your accounts receivable aging and put each expected payment in the week you realistically think it will arrive, not the due date.
• New sales collected. For cash, card, or quick-pay businesses, use a typical weekly amount based on recent history, adjusted for known seasonality.
• Other inflows. Refunds, deposits, a planned owner contribution, or loan proceeds. Only include what you're confident about.

3. Cash out

List what has to be paid, by week:

• Payroll and payroll taxes on your actual pay dates.
• Rent, utilities, insurance, and subscriptions on the weeks they hit.
• Vendor and supplier bills from your accounts payable list, in the week you plan to pay them.
• Loan and credit card payments.
• Tax payments such as sales tax and estimated income tax payments. Ask your preparer for the amounts and dates.
• Owner draws or distributions.
• Planned purchases like equipment, inventory buys, or a vehicle.

4. Net cash flow

For each week: total cash in minus total cash out.

5. Ending cash

Beginning cash plus net cash flow. Add one more row underneath for your minimum cash cushion, the lowest balance you're comfortable holding. Many owners use roughly one payroll plus one month of fixed bills. Then highlight any week where ending cash drops below that line.

Building your first forecast in an hour

1. Start from reconciled books. Your bank balance, receivables, and payables need to be accurate. If the books are behind, the forecast inherits every error. This is the single biggest reason forecasts fail.
2. Pull three lists: open customer invoices, unpaid bills, and recurring payments from the last two or three months of bank statements.
3. Place the big, certain items first: payroll, rent, loan payments, and tax payments.
4. Add receivables realistically. If a customer always pays 15 days late, forecast it 15 days late.
5. Fill in typical weekly sales and spending from recent history.
6. Look for the low point. Which week has the lowest ending cash? That's the week to plan around.

Using it every week

A forecast is only useful if it stays current. Set aside 20 minutes on the same day each week:

• Replace last week's forecast with actual numbers and note what was different.
• Roll the forecast forward by adding a new week 13.
• Update customer payment timing and any new bills.
• Check the low point again.

Over a few months, comparing forecast to actual teaches you a lot: which customers pay slowly, which costs creep, and how much cushion your business actually needs.

What to do when you see a gap

The point of seeing a shortfall eight weeks out is that you still have options. Common levers include:

• Following up on overdue invoices or offering easier ways to pay.
• Asking larger customers for deposits on new work.
• Timing non-urgent purchases or owner draws after the low point.
• Talking with a key vendor about terms before you need it, not after.
• Arranging financing early, while your numbers look healthy. (JRK Financial does not make or arrange loans, but clean books make that conversation with a lender easier.)

Common mistakes

• Forecasting from the P&L. Revenue isn't cash until it's collected. Read how to read a P&L to see why the two differ.
• Forgetting lumpy payments like quarterly taxes, annual insurance, or year-end bonuses.
• Being optimistic about collections. Use real payment habits.
• Building it once and never updating it.

Want someone to keep it for you?

A rolling 13-week cash forecast is part of our Small Business Financial Advisor service: $150 per month for a monthly 30-minute review of your numbers and direct access for cash flow, pricing, and decision questions. When we also keep your books, the forecast is built on accounts we reconcile every month.

To talk about your cash picture, book a free consultation or call or text 269-200-2910.

This article is for general educational purposes only and is not financial, tax, or lending advice.