What to do with surplus cash in a UK limited company

Step 1: Be clear what “surplus” really means

Not all spare cash is surplus.

Split your balance sheet into three pots:

• Working capital: VAT, PAYE, and Corporation Tax dates; regular overheads.
• Planned spending: recruitment, equipment, refurbishments, marketing.
• True surplus: money you can leave invested for 5+ years.

This clarity supports the “wholly and exclusively” test for employer pension funding and helps protect Business Asset Disposal Relief (BADR) by evidencing that cash beyond the runway is genuinely surplus to trade.

Step 2: Park short term money in interest-bearing accounts

Operational cash belongs in business easy access and notice accounts so it works while it waits. These accounts preserve liquidity and can meaningfully reduce the drag of idle balances. 

Large sums should be spread across different authorised firms to stay within the FSCS deposit limits. Many brands share a licence, so check group structures before spreading.

Practical tips

• Use automatic sweeps from current to savings/notice to minimise idle cash.
• Review rates and access terms quarterly; replace expiring bonuses promptly.
• Remember that interest is taxable within the company’s profits.

Step 3: Consider pensions first (often the most efficient)

For many owner-directors, the most tax efficient home for surplus cash is an employer pension contribution paid by the company. 

If made wholly and exclusively for the purposes of the trade, contributions are usually deductible for Corporation Tax. You avoid Income Tax/NI on the way in, and gains grow tax-free inside the pension. It’s good practice to keep board minutes that set out the remuneration policy and business rationale.

Checklist

• Confirm annual allowance and whether carry forward from the previous three tax years is available. GOV.UK
• Note pension access age (normally 55, rising to 57 on 6 April 2028) and treat contributions as long term money set aside for retirement.
• Choose a diversified investment approach aligned to your retirement timeline and risk tolerance.

When pensions may not be first

• If you need liquidity for acquisitions or large expenses
• If contributions would breach tapered/other allowances.
• If you need personal access earlier than pension rules allow.

Step 4: Invest longer term retained profits

With the cash buffer secured, consider deploying multi-year surplus into a diversified portfolio. You can invest inside the trading company or through a separate investment/holding company.

Option A: Invest inside the trading company

This is simple operationally, but growing non-trading assets can weaken the company’s trading status, relevant for BADR on a future share sale. Keep non trading assets proportionate, document why cash is surplus, and monitor the split of activities, assets, and income.

There is no fixed HMRC limit on how much of the company can hold in investment assets before BADR is at risk. Instead, HMRC looks at the overall picture, although levels above 20% are more likely to attract closer scrutiny.

Option B: Use a holding company or investment company 

A separate company can ring fence investment risk away from the trading entity and keep the trading company “pure” for a sale. 

Depending on purpose and activity, you could consider close investment-holding company (CIC) rules and ensure the group structure supports your commercial aims. A holding company that mainly holds shares in trading subsidiaries is typically not a CIC, but structure and documentation matter. Take financial advice before moving funds.

Governance in practice

• Draft an Investment Policy Statement (time horizon, risk budget, permitted instruments, rebalancing rules).
• Keep board minutes and a clear paper trail for transfers and rationale.
• Use professional custody/platforms for corporate accounts and maintain accurate beneficial ownership records.

Specialist option: Corporate owned investment bonds (use selectively)

Corporate owned investment bonds can offer tax deferral in some cases and simplified administration. Outcomes depend on your accounting basis (micro entities using historic cost accounting can differ from larger companies using fair value). 

UK “onshore” bonds carry an internal tax credit and create chargeable events on surrender or withdrawals, which drive the company’s tax point. This is a technical area, so expert financial advice is needed before proceeding.