When a business wants to grow, it needs more capital. That capital might be used to purchase inventory, hire staff, open new locations, or expand into new markets. As businesses scale, funding decisions become more strategic. Capital structure begins to influence cost efficiency, governance, balance sheet resilience, and the pace of growth can be executed.
At this stage, most businesses are choosing between two primary sources of capital: debt financing and equity investment.
Business owners are surprised to learn that debt is cheaper than equity. This is not just financial theory. It shows up clearly in how businesses grow, how much control owners retain, and how quickly capital can be deployed.
To understand why, it helps to think about risk, cost, and speed.
Borrowing Money Versus Selling Part of the Business
A Spanish medical device import from China business. Needs £100K to purchase inventory, pay overseas manufacturers, cover regulatory testing and certification costs, and fund shipping and customs duties before products can be sold.
Option one is that a lender provides £100K and they agree to repay £110K in a few months. Once the loan is repaid, the relationship ends.
Option two is that an investor provides £100K, but in return takes 30% ownership of the business. They receive 30% of future profits and retain that stake if the business grows significantly.
Borrowing money has a clear, time limited cost. Selling part of the business creates a permanent cost.
Debt has a defined, contractual price. Equity has an open ended cost that increases as enterprise value grows. Debt is finite in cost, while equity represents a permanent sharing of future upside.
The Cost of Capital Framework
Every business has a cost of capital, which represents the minimum return required by those who provide funding. This is typically expressed through the weighted average cost of capital, or WACC.
The formula is:
WACC = (E ÷ V × Re) + (D ÷ V × Rd × (1 − T))
Where:
- E is the market value of equity
- D is the market value of debt
- V is total capital, being E plus D
- Re is the cost of equity
- Rd is the cost of debt
- T is the corporate tax rate
The formula highlights two fundamental points. First, equity is more expensive than debt because the cost of equity, Re, is higher than the cost of debt, Rd. Second, interest on debt is tax deductible, which reduces its effective cost after tax. For most SMEs, the cost of senior debt might sit in a range of 6 to 9% depending on credit quality, structure, and jurisdiction. The cost of equity for the same business is often well into the mid-teens or higher, reflecting the risk, illiquidity, and uncertainty borne by equity investors.
Even without optimisation, introducing sensible levels of debt into the capital structure reduces WACC. A lower WACC increases enterprise value and improves the economics of growth investments.
Why Lenders Charge Less Than Investors
The cost difference between debt and equity is driven by risk and position in the capital structure.
Lenders agree interest rates upfront and focus primarily on repayment. Their downside risk is mitigated through contractual terms, security, and priority in insolvency. Equity investors take residual risk. If the business performs poorly, they may lose their entire investment. If it performs well, they expect a significant return. As a result, they target materially higher internal rates of return. A lender might charge 7% interest annually. An equity investor may expect to double or triple their capital over time. That return expectation is the true cost of equity.
Cost of Capital
Businesses talk about cost of capital. This just means how expensive it is to get money. Most finance teams assess funding decisions through the lens of WACC.
Because debt is cheaper and tax deductible, adding debt generally reduces WACC, provided leverage remains within sustainable limits. A lower WACC reduces the hurdle rate for investment decisions and improves valuation outcomes. Projects that may not be viable under an equity-heavy structure become value accretive when funded with appropriately structured debt. This is why mature businesses with predictable cash flows can optimise leverage rather than rely on repeated equity issuance.
Keeping Control of the Business
Money is not the only issue. Control matters.
When a business uses debt, the owners stay in charge. The lender does not usually get a say in daily decisions. They care about being repaid, not about how the business is run day to day. Equity investors, by contrast, seek influence over strategy, governance, and future funding decisions. While this can add value, it also reduces autonomy and can slow execution.
For many growing businesses, keeping control allows faster and clearer decision making.
Growth Is About How Fast Money Moves
Growth is not just about how much money a business has. It is about how quickly that money can be used and reused.
This can be observed through working capital metrics such as the cash conversion cycle, which reflects the time between cash outflows for inputs and cash inflows from customers. Reducing the cash conversion cycle increases capital velocity. Higher capital velocity allows businesses to scale activity without proportionally increasing funding requirements. This idea is sometimes called the speed of capital.
Debt financing supports this model by providing flexible access to liquidity. Revolving credit facilities, invoice finance, and asset based lending allow businesses to fund working capital dynamically and repay borrowings as cash is realised.
Equity capital is slower to deploy and does not flex with operational cycles. As a result, it is less efficient at supporting transactional growth.
For businesses competing in busy markets, speed matters more than perfection.
Why Payments and FX Matter Too
Treasury infrastructure plays a critical role in capital efficiency.
If customers take a long time to pay, cash is stuck. If international payments are slow or expensive, growth is harder. If foreign exchange is badly managed, profits can disappear. Good payment systems help money arrive faster. Good cash management helps leaders see where money is at any moment. Good FX solutions reduce risk when trading across borders.
These tools do not just make things tidy. They help money move faster through the business.
When integrated with debt funding, these tools materially increase capital velocity. Cash is deployed faster, recovered sooner, and redeployed more efficiently. This directly supports scalable growth across multiple geographies.
Using Debt in a Sensible Way
Debt is not magic. It needs to be used carefully.
Borrowing should align with cash flow generation and liquidity capacity. When misused, debt increases financial risk. When used well, it enhances returns, lowers the cost of capital, and supports disciplined expansion. Used well, debt helps businesses grow without giving away ownership. It lowers the overall cost of funding and increases the speed at which money can be put to work.
Final Thoughts
Equity has an important place, especially when a business is very young or taking big risks. But for established businesses, debt is usually cheaper, faster, and more flexible.
It allows owners to keep control, plan costs clearly, and grow at a sensible pace. When combined with strong treasury, payments, and FX solutions, it helps money flow smoothly through the business.
Growth is not just about raising capital. It is about how well that money is used, how quickly it moves, and how much value it creates over time.
