Credit vs Retained Profit
The trade-offs between using your own cash buffer and using someone else's money to grow. How to calculate the real cost of both, and when to use which.
Written by Daniel, peer-reviewed by Marcus
Last reviewed:
Published:
Who this is for: Profitable business owners deciding whether to spend their hard-earned cash reserves or take out a loan/credit facility for their next big step.
The short answer
The true cost of retained profit
Many owners think retained profit is 'free' money because it doesn't have an interest rate attached. This perspective is misleading, as retained profit does have an opportunity cost – it could have been invested elsewhere to yield returns. More critically, it also has a survival cost tied to business vulnerability during unforeseen circumstances.
Draining your £20,000 cash buffer could leave you exposed. Imagine using it to purchase new equipment, only to find that your biggest client suddenly cancels a contract. With no financial cushion, your business's operational resilience is compromised – that's the real cost of depleting retained profits.
Using retained profits should be a strategic choice, taking into account your business’s current and future cash flow needs. Without careful consideration, you risk sacrificing potential growth opportunities and long-term stability.
The true cost of credit
Credit, whether it's through loans, overdrafts, or credit cards, preserves your cash buffer, which is its primary advantage. By using external funding, you maintain your financial safety net for unexpected challenges.
However, the allure of credit comes with costs: both explicit financial costs such as interest rates and fees, and more subtle, structural costs such as rigid repayment schedules. The financial strategy must consider if the new equipment, funded by credit, is likely to generate sufficient revenue to cover ongoing repayments.
A mismatch in timing—where repayments begin before the investments generate returns—can strain cash flow and hinder business financial health. Thus, ensuring alignment between repayment schedules and revenue generation is vital.
The matching principle
Applying the matching principle means aligning the source of funding with the asset's lifespan and risk level. This principle aids in making more informed financial decisions that suit the business's unique needs and timelines.
Short-term, highly predictable financial requirements, such as purchasing inventory for a signed order, are ideal for short-term credit sources like a line of credit. These are low-risk investments with assured returns.
Conversely, long-term, speculative ventures such as entering a new market or a full-scale rebrand should typically be bankrolled by retained profits. These are inherently riskier and relying on credit could result in financial strain if the venture doesn't deliver anticipated results.
Worked example: Funding a £15,000 marketing campaign
- The Investment
- £15,000 on a new digital marketing push.
- The Return Profile
- Highly uncertain. May take 6 months to show ROI, may fail entirely.
- Option A: Retained Profit
- Buffer drops by £15,000. If campaign fails, the money is gone, but the business survives.
- Option B: 12-Month Loan
- Buffer preserved. Repayments of £1,350/month begin immediately.
- The Danger of Option B
- If the campaign fails, the business still has to find £1,350 every month, severely damaging ongoing cash flow.
Illustrative example. Because marketing is speculative, Option A (Retained Profit) is the much safer choice, provided the business still has a minimum survival buffer left over. This way, even if the campaign doesn’t yield immediate results, the business’s near-term survival isn’t jeopardized.
What to do, in order
- 1
Assess the certainty of the return
Consider whether this investment has a guaranteed return, like fulfilling a signed contract, or if it’s more speculative. Speculative investments carry higher risk and thus should rarely be funded by credit, which demands regular repayments regardless of success.
- 2
Check your buffer floor
Determine if using retained profit would reduce your cash reserves below your minimum survival threshold. As a guideline, ensure you have reserves for at least three months of fixed costs to safeguard your business against unforeseen situations.
- 3
Calculate the 'cash drag' of credit
Carefully project your monthly loan repayments against the anticipated cash inflow from this investment. The aim is to ensure that any new revenue will adequately cover the repayment amount, thereby mitigating the financial strain on your cash flow.
- 4
Compare total cost of credit
When opting for credit, it’s essential to evaluate the Total Amount Payable, not just the APR. Consider all associated fees and setup costs as these directly impact the overall expense of the credit facility.
Common mistakes
- Using expensive short-term credit to fund long-term speculative growth.
- Draining the entire cash buffer to zero to avoid paying a small amount of interest on a loan.
- Taking a loan because the monthly repayment 'looks small', without calculating the total cost over five years.
- Misjudging credit terms and failing to align repayment schedules with expected cash returns, leading to liquidity crises.
- Ignoring alternative financing options due to fear of interest rates, potentially missing out on strategic growth opportunities that credit could safely fund.
If you only have five minutes
Frequently asked questions
- Should I ever use a personal loan for my business?
- It is highly risky. A personal loan makes you personally liable for the debt, piercing the protection of a limited company. If the business fails, you still have to pay the loan from your personal income, which could have devastating personal financial consequences.
- What is the cheapest form of business credit?
- It varies, but generally secured loans, such as asset finance that uses a vehicle or equipment as collateral, tend to offer lower interest rates compared to unsecured term loans. Business credit cards or overdrafts often come with higher rates. However, it's crucial to consider whether the timing and terms align with your business's cash flow needs.
- Can using credit improve my business credit score?
- Yes, responsibly using and repaying credit can build your business credit score. This can be advantageous for future borrowing, as lenders often offer better terms to businesses with established and strong credit histories. It's important to manage the credit carefully to avoid any negative impact on your credit score.
- How do I decide which form of credit to choose?
- This depends on several factors including the amount needed, the repayment period, the purpose of the loan, and your current financial situation. It’s wise to compare various credit products and consider consulting with a financial adviser to ensure alignment with your business goals.
- Are there tax implications for using retained profits?
- Retained profits are already taxed when they were initially earned. However, using them doesn’t create additional tax liabilities on their own. That said, significant changes in retained earnings might affect dividend payouts and tax treatment, so it’s best to consult with a tax adviser for personalized advice.
Sources
Who wrote and checked this
Written by Daniel Mercer, who has run the numbers on his own small business and writes from that experience. Daniel is not an accountant or a regulated financial adviser. Who writes this site.
Peer reviewed by Marcus Thorne, Small Business Advisor. Peer reviewers check for technical accuracy and compliance with current UK regulations.
Last reviewed: 29 July 2026
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