Managing Cash Flow in a High-Growth Product Business

High growth is supposed to be the goal. So why does it so often feel like a financial emergency?

It's a question I hear regularly from CPG founders who are experiencing strong sales growth but finding that their Profit First allocations never seem to cover costs. The reason is structural: in a high-growth product business, your materials and production costs increase faster than your revenue, because you're building inventory ahead of sales. You're funding future demand from current cash flow.

This problem is compounded by seasonality — think high gift-giving in Q4 — and lumpy purchasing of ingredients and packaging runs.

Here's the system I recommend.

1. Smooth seasonal revenue with a vault account

Calculate your annualised revenues as a monthly average. When high season starts and revenue exceeds that average, open a "vault" account and deposit the excess there. When you're in the slow season, drip the vault balance back into your operating accounts to smooth the incoming revenue.

This prevents the whiplash of feast-and-famine cash flow and gives you a consistent base to allocate from.

2. Separate baseline COGS from growth COGS

In high-growth mode, not all of your inventory spend is the same. Split your costs into two categories:

Baseline COGS — the direct variable costs per sale. What it actually costs to fulfil an order right now.

Growth COGS (Strategic Inventory) — extra stock, packaging, or raw materials purchased ahead of forecasted demand.

Keep Baseline COGS in your regular Materials/COGS allocation, funded at a higher percentage than your CAPS to stay ahead of the growth curve.

3. Create a Growth Reserve account

Fund a separate Growth Reserve account with a small percentage of revenue — 5 to 10% — during growth periods. This is where you bank funds for those front-loaded inventory investments.

Without the Growth Reserve, a large ingredient or packaging purchase will wipe out your monthly cash flow and force you to pull from OpEx. With it, production doesn't touch your main operations — the funds are already set aside, and the process stays smooth, predictable, and calm.

The bottom line

Cash flow forecasting tied to high-growth inventory planning is one of the most critical skills a product founder can develop. The vault account, the COGS split, and the Growth Reserve aren't complex — but they require intentionality and consistent execution.

If you're in a high-growth phase and finding that your cash flow system isn't keeping up, these three adjustments will change the picture significantly.