What it means
Growth costs money before it pays money. Selling more usually means holding more stock, waiting longer for customers to settle their bills and buying more equipment, and all of that has to be funded before the extra profit lands in the bank.
The internal growth rate puts a number on how much of that expansion a business can finance from profits it has already earned and chosen to keep. The measure matters because it separates ambition from arithmetic.
A board can set a 25% growth target, but if the internal growth rate is 6%, the missing 19 percentage points have to come from a lender, an investor, or a genuine change in how the business operates. Two levers drive the figure: how much profit the company's assets generate, and how much of that profit stays inside the business rather than leaving as dividends.
Pulling either lever raises the ceiling, which is why fast-growing private companies so often pay their owners nothing at all for several years. In practice, finance teams place the internal growth rate next to the sales growth built into the budget.
If planned growth is higher, the plan needs an explicit funding line, a tighter working capital cycle, or a smaller payout to owners. One common point of confusion is the sustainable growth rate, a close cousin that allows borrowing to rise in step with equity.
The internal growth rate is the stricter of the two and is always the lower number, because it assumes no new debt whatsoever.
In practice
Real-world examples.
Example
A family-owned bakery chain wants to add four stores next year, a 30% jump in sales. Its internal growth rate is 7%, so the finance director tells the family that either the dividend stops for two years or the expansion is funded with a bank facility.
Example
A software reseller earns a return on assets of 15% and retains all of its profit. Its internal growth rate works out near 18%, comfortably above the 12% growth in the sales plan, so the board approves the budget without arranging extra finance.
Example
A packaging manufacturer sees its internal growth rate fall from 9% to 4% after a poor year. Management responds by cutting slow-moving stock and chasing overdue invoices, which lifts return on assets and restores headroom for growth the following year.
Think of it
“Internal growth rate is your speed limit when relying entirely on your own generated resources.
Formula
Calculation
Internal growth rate = (Return on assets x Retention ratio) / (1 - (Return on assets x Retention ratio))
Retention ratio = 1 - dividend payout ratio.
Take a distributor with net profit of $200,000, total assets of $2,000,000 and dividends of $80,000 paid to its owners.
Return on assets = $200,000 / $2,000,000 = 0.10, or 10%.
Retention ratio = ($200,000 - $80,000) / $200,000 = 0.60, or 60%.
Return on assets x retention ratio = 0.10 x 0.60 = 0.06.
Internal growth rate = 0.06 / (1 - 0.06) = 0.06 / 0.94 = 0.0638, or roughly 6.4%.
If current sales are $3,000,000, the company can support about $3,191,000 of sales next year without a single dollar of new funding. Everything above that figure needs a loan, an equity injection, or a lower dividend.Case study
Seen in the real world.
Brightwater Ceramics is an illustrative company invented to show the idea in action. The tile maker had sales of $6,000,000, retained 70% of a $420,000 profit and held $4,200,000 of assets, giving an internal growth rate of a little under 8%. The sales director, encouraged by a large hospitality contract, pushed a plan for 22% growth.
The finance lead mapped the gap. Growing at 22% would require roughly $600,000 of extra stock and customer balances that the retained profit could not cover, leaving the company short of cash by the fourth month of the plan.
The board kept the contract but staged it over eighteen months, suspended the dividend for one year and negotiated an invoice finance line for the peak. Growth came in at 19% and the overdraft was never breached, which the directors credited to having the ceiling calculated before the plan was signed off.
Watch out
Common mistakes.
- Treating the internal growth rate as a forecast of what will happen, when it is a funding ceiling that describes what can happen without outside money.
- Confusing it with the sustainable growth rate, which permits proportional new borrowing and therefore produces a higher number.
- Using profit after an unusual one-off gain in the calculation, which flatters return on assets and overstates the achievable pace of growth.
Questions
People also ask.
Can a business grow faster than its internal growth rate?
Yes, but only by raising debt or equity, selling assets, or improving profitability and the working capital cycle.
Does a high internal growth rate always mean the company is healthy?
No, it can simply reflect a business that pays no dividends, and it says nothing about whether there is demand for the extra sales.
How often should the figure be recalculated?
Once a year alongside the budget is normal, with a fresh calculation whenever profitability or the dividend policy changes materially.
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