13-Week Cash Flow Forecast
Definition
A week-by-week projection of cash in and cash out for the next quarter. It is the most practical tool for timing inventory purchases, tax payments and payroll without surprises.
Want a deeper explanation?
Formula
Ending Cash (week) = Beginning Cash + Expected Receipts − Expected PaymentsA 13-week forecast is short enough to be accurate and long enough to see trouble coming. It lists actual expected payouts, purchase order deposits, payroll, loan payments and taxes week by week, so a crunch shows up weeks in advance instead of the day it happens.
It works best when it is updated every week and compared against what actually happened. Watch for: any week where projected cash dips below your minimum floor, because that is your signal to move a payment or line up financing.
Example
The forecast shows a $60,000 PO deposit and a quarterly tax payment landing in week 6, dropping cash below your $25,000 floor, so you shift the deposit two weeks.