13-week cash plan: the founder's methodology in tense periods (2026 guide)

The 13-week cash plan — known internationally as the TWCF (Treasury Weekly Cash Forecast) — has become the reference format in finance functions during tense periods. While the annual monthly plan answers a budget logic, and a rolling monthly plan suffices in controlled growth, the 13-week weekly format matches a specific horizon: long enough to anticipate major deadlines (quarterly VAT, payroll taxes, rent, payroll, corporate tax), short enough to stay precise and operational.

Thirteen weeks represents roughly a quarter: the horizon over which cash variations are predictable but where corrective decisions are still possible. A 6-month plan is too late to react, a 4-week plan too short to anticipate. The 13-week plan was adopted by turnaround funds, mid-cap finance functions and most restructuring consultancies. It is now accessible to SMEs through tools connected to accounting.

For a broader cash framing, see our 2026 cash management founder's guide and our complete cash management methodology.

The 13-week plan is not a permanent format for every company. It becomes relevant as soon as one of three triggers is present:

1. Active cash tension: available cash represents less than 60 days of fixed costs; recurring overdraft appears; a tax or social-security deferral has been requested.
2. Commercial uncertainty: sector downturn, key-customer loss in discussion, heavy growth project.
3. Restructuring or sale phase: acquirers and funds expect this format. Its presence accelerates due diligence.

In stable growth with cash above six months of fixed costs, a 12-month monthly plan remains sufficient. The 13-week plan complements, not replaces, it.

The 13-week plan is built around a single table where each column represents a calendar week (W, W+1, …, W+12). Lines are organised in six blocks.

Block 1 — Receipts#

Block 2 — Disbursements#

Block 3 — Net weekly cash variation#

Receipts minus disbursements for the week.

Block 4 — Cash available at start and end of week#

Block 5 — Operating reserve and alert#

An operating reserve must be preserved — typically the amount needed to cover the next payroll, the current quarter's payroll taxes and one month of rent. If end-of-week cash drops below this reserve, an alert is automatically triggered (red conditional formatting in the spreadsheet).

Block 6 — Off-balance-sheet commitments and mobilisable lines#

Undrawn mobilisable lines (Dailly, factoring, authorised overdraft) must appear at the bottom of the table, week by week. This makes it possible to compute total available liquidity by distinguishing real cash from accessible lines. The distinction is critical in tense periods: a theoretically available line can be suspended by the bank without notice.

1. Strict weekly granularity#

Every flow is positioned in the week of its actual disbursement or receipt, not the week of the invoice. An invoice issued in W1 with a 6-week DSO appears in W7 receipts. A supplier invoice received in W3 with an 8-week DPO appears in W11 disbursements.

This granularity changes everything. It exposes point-in-time peaks invisible in a monthly plan — for instance the same-week concentration of quarterly VAT, payroll, loan repayment and a strategic supplier payment.

2. Weekly rolling forecast#

Every Monday (or Tuesday morning), the plan is updated: the past week is frozen as actual, a new week is added at the horizon. The table always carries 13 rolling weeks ahead.

The rolling logic detects forecast-vs-actual gaps. If each week the forecast underestimates receipts by 5%, that is an alert on model quality or on a structural shift (DSO lengthening, commercial deterioration).

3. Distinguish confirmed from estimated#

Each receipt and disbursement line must be typed:

• Confirmed (issued invoice, signed contract, known tax deadline);
• Probable (commercial forecast with history);
• Estimated (target, hypothesis).

The conservative scenario keeps only confirmed + probable. The optimistic scenario adds estimated. In a tense period, steering relies exclusively on the conservative scenario.

Educational case (illustrative figures, adapt to your situation).

An industrial SME with €12M revenue, 35 employees, 60-day DSO, 45-day DPO, starts its 13-week plan at the end of April.

Initial assumptions:

• W1 starting cash: €380k + authorised €200k undrawn Dailly line;
• operating reserve: €320k (payroll + payroll taxes + rent);
• seasonality: peak in June-July, trough in August.

Detection in W5: projected cash drops below the operating reserve between W8 and W10 due to:

• a €90k CAPEX down payment (W8);
• quarterly VAT of €110k (W9);
• a probable late payment from a key customer (W8-W9).

Decisions taken in W5 (anticipation):

• shifting the CAPEX down payment to W12 (negotiated with the supplier);
• accelerating collection on the key customer (targeted chasing, conditional 1% discount for 10-day payment);
• preparing the Dailly drawdown (signed slip ready to activate).

Outcome in W10: cash stays above reserve, the Dailly line is ultimately not drawn. Decisions were taken before the tension peak, not during.

Without the 13-week plan, the peak would only have appeared in W8 on the bank statement. Three weeks would have been lost.

SaaS and recurring subscriptions#

Receipts are 95% predictable via MRR and churn tracking. Weekly granularity stays useful for disbursement peaks (payroll, social security, cloud hosting, payment commissions). The rupture scenario (loss of a customer representing > 20% of MRR) must be systematically modelled. See our article on startup burn rate and 90-day plan 2026.

E-commerce#

Weekly seasonality is high (Black Friday, sales, holidays). The 13-week plan must include collection delays by payment method: D+1 for Stripe or Adyen, D+30 for BNPL, variable for marketplaces. Inventory purchases must be modelled with their forward seasonality (orders 8 to 12 weeks before sale). See our e-commerce sector page.

Construction#

The cycle is long (several months between order and invoicing). Work-progress invoices, retentions and final accounts create cash gaps that the 13-week plan must model line by line. See our construction sector page.

Distribution and physical retail#

Cash follows weekly footfall. The plan must include inventory turnover and restock peaks. See our retail and commerce sector page.

Hospitality and restaurants#

Near-daily receipts but heavy payroll and food inventory. The 13-week plan must model VAT peaks (mixed 5.5% / 10% / 20% regime in France) and supplier advances.

See our reviews of Pennylane, Power BI and Finthesis.

Practical recommendation: do not start with the tool. Build the methodology on a spreadsheet first, validate line relevance and update cadence, then migrate to a dedicated tool once the format stabilises. Tooling failures almost always come from an unproven methodology.

Common mistake: leaving the 13-week plan to the bookkeeper alone. It then becomes a technical exercise, not a decision tool. The weekly leadership review is non-negotiable. For SMEs without an internal CFO, see our outsourced CFO service for startups and SMEs.

The 13-week plan does not replace the annual budget or the strategic business plan. It complements them:

• the strategic business plan (3 to 5 years) frames trajectory and fundraising;
• the monthly annual budget frames resource allocation and KPIs;
• the 13-week plan secures operational cash execution.

The three must be consistent. A structural gap between the actual 13-week plan and the monthly budget signals either an execution problem or an unrealistic budget to revise. See our article forecast balance sheet and budget steering.

1. Confusing invoice date with flow date: VAT and DSO create gaps that destroy the forecast.
2. Forgetting off-balance-sheet items: long-term lease commitments, given guarantees, ongoing litigation.
3. Failing to type flows (confirmed/probable/estimated): everything blurs, and so do decisions.
4. Updating monthly: the 13-week plan loses 80% of its value without weekly rolling.
5. Omitting the operating reserve: a plan that hits zero alerts on nothing; a plan that drops below the reserve alerts three weeks before the crisis.
6. Deploying the tool without the methodology: Pennylane + a treasury module without governance is cost without value.
7. Systematic commercial optimism: overestimating receipts by 10% over 13 weeks creates an invisible breaking point.

The 13-week plan must integrate the main French regulatory deadlines:

• VAT: chargeable on collection for services (election), on invoicing for goods (BOFiP, BOI-TVA-BASE-20). Filings are monthly, quarterly or annual depending on thresholds.
• Corporate income tax instalments: 15 March, 15 June, 15 September, 15 December. Balance within 3 months and 15 days of year-end.
• Payroll taxes: monthly Urssaf on the 5th or 15th depending on headcount; quarterly contributions for very small structures.
• Payment terms: 60 days from invoice or 45 days end of month (Code de commerce L441-10), to integrate as a legal constraint, not a steering variable.
• Local business taxes (CFE) and property tax: 15 December.

This list is not exhaustive. The plan must include deadlines specific to the company's tax regime (VAT-on-payroll tax, royalties, etc.).

The 13-week plan often reveals a short-term financing need. The hierarchy stays constant:

1. Working-capital optimisation first (no cost) — see our article 9 levers to free cash.
2. Existing mobilisable lines (overdraft, Dailly, in-place factoring).
3. Opening new lines — see our comparison factoring, Dailly, RBF.
4. Long-term refinancing or shareholder injection.

Before any financing, the 13-week plan quantifies the need precisely and enables objective negotiation with the bank or an investor.

The 13-week plan in central scenario is not enough in tense periods. It must be paired with a degraded scenario (revenue -15 to -25%, DSO +15 to +30 days) and a rupture scenario (revenue -35 to -50%). For methodology, see our article cash stress test.

Concrete integration: add a second and third sheet with the same structure to the spreadsheet, applying degraded assumptions. Compare end-of-week cash curves across the three scenarios.

Three observations from our practice:

1. The 13-week plan is rarely the technical difficulty. The structure is built in two or three days. The difficulty is weekly discipline and the managerial culture of cash decision-making.
2. Tools do not replace methodology. Pennylane, Agicap or Power BI are excellent accelerators after the methodology is validated. Before, they relocate the problem without solving it.
3. The banking-relationship effect is underestimated. An SME presenting its bank with a held and updated 13-week plan changes category in the relationship manager's informal scoring. It is a measurable relational asset.

The major risk is not the plan itself — it is the abandonment when tension eases. Many companies build a 13-week plan in crisis, hold it for six months, then drop it on return to normal. Format is lost, methodology too. When the next tension arrives, everything must be rebuilt.

Mitigation: keep the 13-week plan in simplified format in normal periods (bi-weekly update, lighter governance), and reactivate full cadence as soon as a trigger returns.

Before deploying the 13-week plan, the founder must answer:

• What are my observed DSO and DPO over the past 12 months?
• What is my minimum operating reserve?
• What mobilisable lines do I have, and on what conditions?
• Who runs the weekly update and who approves arbitrations?
• Which tool will be used in phase 1 (spreadsheet) then phase 2 (dedicated tool)?

• E-invoicing: the 2026-2027 French rollout reshapes invoice rhythm and traceability. See our e-invoicing service.
• Progressive PGE exit: integrate ongoing repayments in the central scenario.
• Higher rates: model variable-rate debt with a high assumption.
• Customer concentration: monitor the top-5 share of collected revenue.
• CSRD and reporting: certain non-financial obligations may affect customer relationships (loss of public contracts on non-compliance).

• Observed DSO and DPO measured over 12 months
• Minimum operating reserve quantified
• Structured 13-week table (6 blocks, 13 columns)
• Flows typed confirmed / probable / estimated
• Weekly update scheduled (fixed day)
• Founder or CFO weekly review scheduled (30 minutes)
• Mobilisable lines documented (Dailly, factoring, overdraft)
• Operating reserve visible with conditional alert
• Degraded and rupture scenarios in separate sheets
• Target tool defined after methodology validation