The 13-Week Cash Forecast: How to Actually Build (and Maintain) One
Collated by Paul Jung, CFA
Curated by Rubric Financial
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Why 13 Weeks (And Not 12 or 16)
- 13 weeks ≈ one fiscal quarter. Long enough to capture all the recurring expense cycles (monthly payroll, quarterly tax estimates, mid-quarter rent + insurance) and a typical accounts receivable cycle. Short enough that you can update it weekly without it becoming a maintenance burden.
- The output is a SINGLE NUMBER each week: ending cash balance. If that number trends to zero before week 13, you have a runway problem, and you know exactly when.
- Used by: board members to validate runway, founders to plan hires + spend, lenders + investors during diligence, and operating teams during cash-tight periods.
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