How to improve cash flow in a small UK business: practical steps and the numbers behind late payment

A profitable business can run out of cash on a Tuesday, usually because a customer has not paid an invoice that fell due last week. The quickest way to improve your cash flow is to close the gap between doing the work and being paid. Invoice on the day of delivery, write short payment terms down, take deposits where the trade allows, and chase on the first day an invoice is late. Then create a cash flow forecast that runs 13 weeks ahead, so you see a shortfall before it arrives, and borrow only against what is left.

Key Takeaways

Understand your cash flow: cash flow and profit are not the same thing

Profit is what is left of your revenue after costs. Cash flow is the money actually moving in and out of the business in a given period. A business may be profitable on paper and still be unable to pay its bills, because the money it has earned has not arrived yet. If you have paid for materials and wages to deliver a job and the customer has not paid, you have made a sale and have less cash than before.

Positive cash flow means more money is coming in than going out. Negative cash flow is the reverse, and a sustained run of it makes it harder to pay bills and cover other expenses. Your net cash for a period is the total of your cash inflow less your cash outflow. Healthy cash flow is not a single good month. It is a pattern where the money arrives before the obligations fall due, or close enough that a buffer covers the difference.

The cash flow statement in your accounts sorts cash into three groups:

• Operating: customer receipts, expenses and the money tied up in working capital.
• Investing: buying long-term assets such as property or equipment.
• Financing: taking out and repaying loans, issuing equity and paying dividends.

The statement looks backwards and tells you what happened. A forecast looks forward and tells you what is coming, which is the part you can still change.

Growth makes things harder, not easier. Each sale has to be funded from available cash, you have to carry stock to grow, and customers usually buy on credit. A business that doubles its orders can need more working capital to deliver them than it had before. To understand your cash flow, ask two questions about every line: when does the cash arrive, and when does the bill fall due?

Other common causes of cash flow issues are a large customer paying late or not at all, changes in the price of stock or raw materials, losing a major customer, a downturn in trading conditions, and narrow margins that leave little room when income dips or costs rise. Relying on a few customers is a particular risk. If one of them cuts its orders or stops buying, you need to know whether the rest of your income could keep the business running.

Small business cash flow: the numbers behind late payment

These are the figures worth knowing, with what each one measures.

What it measures	Figure	Date
Cost of late payment to the UK economy, per year	£11 billion	Government research, quoted by the Small Business Commissioner
Invoices large businesses paid late	15%, down from 25% in 2018	2025
Average late payments owed to a UK small business	About £22,000, or 18% of invoices	2023
Annual cost to SMEs of extra finance to cover late-payment shortfalls	£684m	Research cited by the Small Business Commissioner
Companies that experienced late payments in the past year	90%, with an average delay of 32 days	Late 2025
Firms spending time chasing overdue payments	63%, costing up to £5,200 a year in lost time and resources	Reported February 2026

Three things follow from this.

First, the trend among large businesses is better, but the problem has not gone away. A 15% late rate means roughly one invoice in seven from the biggest payers still arrives after its due date. Manufacturing consistently reports the longest payment times and the highest share of late invoices, and London has the shortest payment times. If you supply manufacturers, plan for slower cash than the national picture suggests.

Second, the cost is not only the delay. It is the time you spend chasing, and the borrowing you take on to cover the wait. The £684m a year that SMEs spend on extra finance to bridge late payment is money paid to lenders for a problem a customer created.

Third, the human cost is real. The Small Business Commissioner has recovered more than £10 million for small businesses since 2017. One four-person IT firm it helped said the recovered payment meant they could make payroll that month. That is the point at which a late invoice becomes a staffing problem.

Five ways to improve business cash flow this month

If you only have an afternoon, start here. Each point is covered in more detail below.

1. Invoice on the day you deliver, and chase on the first day an invoice is overdue.
2. Shorten your payment terms and write the consequences of lateness into them.
3. Take a deposit and make it easy to pay by card or online.
4. Release cash trapped in stock and unused assets, and ask suppliers for longer terms.
5. Forecast 13 weeks ahead and hold a cash reserve so a late payment does not become a crisis.

Business cash flow starts with the invoice

An invoice sent a week late is a payment a week late. Send it on the day you deliver the goods or complete the work, or on the day a milestone is reached.

Before you send it, check that it contains everything the customer needs to pay and that it goes to the right person. Customers do not always tell you an invoice was wrong. They may simply leave it unpaid, and you find out at the chasing stage. The three checks are:

• The invoice has all the details needed for payment.
• It was sent to the right person.
• It was actually received.

Timing matters too. Invoicing at the very end of the month rather than the start can stop you being pushed into the next customer's payment cycle. If a customer pays on a monthly run, an invoice that misses the cut-off by a day can wait a whole month.

A simple tracker is enough. Use a spreadsheet or accounting software that shows the due date for every invoice and flags the late ones, so you know the day an invoice becomes overdue and do not find out from your bank balance.

Payment terms that give you better cash flow

Payment terms are the cheapest cash flow tool you own. The law frames what you can agree:

• If you agree a payment date, it must usually be within 30 days for public authorities or 60 days for business transactions.
• You can agree longer than 60 days between businesses, but it must be fair to both.
• If you do not agree a date, payment is late 30 days after the customer gets the invoice or you deliver the goods or service, whichever is later.

Within that, you choose your own terms. Ways to tighten them:

• Shorten terms, for example from 30 days to 14 days.
• Write due upon receipt on the invoice instead of payment due within 30 days.
• Request part of the payment before you start work, if the customer and the trade allow it.
• Put late payment fees into the original agreement rather than adding them afterwards.

What shorter terms are worth. Take a business invoicing £60,000 over a 30-day month, so about £2,000 a day. If customers moved from 30-day terms to 14-day terms and actually paid on time, you would collect 16 days sooner. That is 16 × £2,000 = £32,000 released from your debtor ledger, once. It is not extra profit. It is cash you stop having to borrow or find elsewhere.

The practical catch is delay. If the average late payer is 32 days past due, a 30-day invoice is paid around day 62. Shorter terms only help if you enforce them, which is the next section.

Business credit: check customers before you offer terms

Every set of payment terms is an extension of credit to a customer. Before you give it, check who you are dealing with, unless they are paying in advance. A business credit report on a new customer costs far less than a debt you cannot collect. The main credit bureaus provide these reports. If the customer is a sole-owner business, the owner's personal credit rating can also tell you something about how likely they are to pay promptly.

Set a credit limit for each customer and review your credit control policy as the business changes. No business wants to turn away trade, but a robust credit checking procedure before you offer terms is what protects the sales you do make.

Chase early, and manage cash flow with the interest you are owed

The most common failure in chasing is waiting. An invoice that is three days late and unchased is quietly being treated as optional.

A sensible order:

1. Check your own side. Confirm the invoice was correct, sent to the right person and received.
2. Contact the customer informally. Phone or email to say payment is now overdue. Ask when it will be paid and who is dealing with it.
3. Say what you can do. Tell them you can charge interest or stop supply, and that you will take further action if needed.
4. Decide what you are prepared to spend. Before escalating, work out how much time and money recovering the debt is worth to you.

The survey figures show what small businesses actually do. Reminders are the most common step, used by 48%. Chasing directly by phone or email comes next at 44%. Withholding other pending goods or services is used by 29%, and charging a late payment fee by 28%. 14% are prepared to take legal action and 11% plan to use a debt collection agency.

Statutory interest. If another business is late paying you for goods or a service, you can claim interest and debt recovery costs. The rate of interest and the fixed sums for recovery costs are set out in the legislation, and the amounts depend on the size of the debt. Check the current figures on GOV.UK before you quote them to a customer, and state in your terms that you will claim them. A customer is far more likely to pay when the invoice already says what lateness costs.

If the customer is a much larger business. The Small Business Commissioner investigates complaints from small businesses about late and overdue payments by larger organisations, and gives advice and support. It exists for exactly the case where your emails and calls have been ignored. Also check whether your large customers have signed the Fair Payment Code, which the Commissioner manages. Gold status needs at least 95% of invoices paid within 30 days, and Silver needs 95% within 60 days. The government has also introduced the Commercial Payments (Late Payments) Bill, which it describes as the most significant reform of payment practices in over 25 years.

Deposits, upfront payments and ways to pay

The best receivable is one you never have to chase. Where the trade allows it, ask for a deposit or part payment before work starts. A deposit does two jobs. It funds the early costs, and it tells you the customer is serious. If your margins can bear it, you can also offer a discount for early payment to selected customers. For some customers that is cheaper than borrowing against the invoice.

Make paying easy:

• Offer several routes: card, online payment and bank transfer.
• Put a payment link on the invoice so the customer can pay from the email.
• Connect your card reader or payment system to your accounting software and business banking, so receipts are recorded automatically.
• If you bill the same customers repeatedly, ask your bank or provider whether collecting by direct debit suits you. Fees and set-up vary by provider.

Online payment cuts out the delay of sending an invoice and waiting for a cheque or manual transfer. It can also raise sales, because customers who can pay immediately do.

Stock, supplier terms and cash management

The other half of cash flow is when you pay out. Good cash management means looking at three areas this month.

Stock. Overbuying creates a liquidity problem, because stock you cannot sell quickly does not turn into cash. Old and excess inventory ties up capital. You can clear it by discounting, selling through online marketplaces or bundling items together. Selling something at a lower margin this month is often better than holding it for a better price while you borrow.

Supplier terms. Ask whether you are paying suppliers too soon, and whether longer terms are available. Your largest customers may ask you for extended terms, so it is reasonable to seek favourable terms from your largest suppliers too. Pooling buying power with other small businesses through a buying cooperative can also win discounts usually reserved for larger firms. Do not stretch suppliers so far that you damage trust. Damaged supplier relationships are one of the first consequences of cash flow problems.

Costs. Review recurring costs, starting with subscriptions you no longer use. Review your prices too. Small, deliberate increases may be possible without hurting demand if your product or service offers clear value.

Positive cash flow from assets you are not using

Could you sell under-used assets to generate cash? Yes, and it is often overlooked. Assets that are unproductive or no longer used can be sold. Assets you still need can be sold and leased back, which raises cash while leaving you with the use of the equipment. Machinery, equipment, computers, phone systems and even office furniture can all be treated this way.

Leasing instead of buying new equipment or vehicles has a similar effect on positive cash flow. It spreads the cost into smaller fixed payments and can make budgeting easier. It can also cost more overall, so compare the total cost before you commit. For items that lose value quickly, such as IT equipment and vehicles, leasing is often worth considering.

Build a 13-week cash flow forecast

Thirteen weeks is one quarter, which is long enough to see most problems coming and short enough to forecast with some confidence. A forecast can cover anything from a few weeks to a year, and the further ahead you look, the less accurate it gets. Many businesses use a rolling forecast, adjusting it weekly or monthly so that it stays current. The biggest benefit is clarity. You can make decisions now, before a shortfall becomes critical.

To manage your cash flow week by week, build it with one column per week and these rows:

• Opening bank balance.
• Cash in. Customer receipts on the dates you realistically expect them, not the due dates on the invoices. Add any deposits, loan drawdowns or other inflows.
• Cash out. Wages, rent, supplier payments, loan repayments, and tax bills on the dates they fall due.
• Closing balance, which becomes next week's opening balance.

Be conservative. Overestimating income is a common mistake and leads to overspending and shortfalls in working capital. Use the dates customers actually pay, not the dates you wish they would.

A worked example. The numbers below are invented to show the mechanics.

Week	Opening	Cash in	Cash out	Closing
1	£18,000	£9,000	£14,500	£12,500
2	£12,500	£6,000	£9,000	£9,500
3	£9,500	£4,000	£11,000	£2,500
4	£2,500	£16,000	£8,000	£10,500

Over four weeks this business takes in £35,000 and pays out £42,500, yet ends the month with £10,500 in the bank. A monthly profit and loss would hide the real problem, which is week 3. The £16,000 customer receipt arrives in week 4, after payroll has gone out, and the balance drops to £2,500. Now you have time to act. A £5,000 deposit on a new job, a request to the large customer to pay one week earlier, or asking one supplier to move a payment back a week would each remove the dip.

Direct or indirect forecasting? A direct forecast lists the actual receipts and payments you expect, week by week, as in the table above. An indirect forecast starts from forecast profit and adjusts for changes in debtors, stock, creditors and non-cash items. For a 13-week view, the direct method suits most owner-managed businesses better, because it shows the day-to-day timing that causes problems. The indirect method is more useful for longer-range planning, where you want the forecast to tie back to your accounts.

At the end of each month, compare the forecast with what actually happened. If you overspent or underspent, adjust the forecast. The review also shows idle cash that could be used better and savings you had not spotted. Cloud accounting software and other tools can automate much of this, and are worth using if you find the spreadsheet falling behind.

Build a cash reserve

A forecast tells you when cash is short. A cash reserve is what lets you absorb a shortfall without panic. As a floor, keep enough cash to cover all your costs for at least a month. A move from one month's available cash to two or three months' is a sensible target, and it is worth every business owner agreeing it as a goal across the team.

Hold the reserve in a business savings account that earns interest, while making sure you can still reach the money quickly if you need it. Even modest returns help over time, and it is a small change that makes the reserve more productive without adding risk.

Five working rules of cash flow

1. Know your cash position every week. Your cash position is the balance you have today plus what is due in and out soon.
2. Invoice at once and collect on time.
3. Pay on the due date, not before, unless an early payment discount is worth more than the cash.
4. Hold a reserve before you need it.
5. Forecast, then compare with what happened, and adjust.

These also answer a common question: how do you avoid working capital shortfalls and keep cash flow steady? You cannot remove every surprise. You can see most of them coming with a forecast, and cover the rest with a reserve and finance you arranged before the pressure arrived. Planning ahead for seasonal swings also helps. Your own past sales are the best guide to when demand rises and falls.

HMRC payments

Tax bills are the cash outflows that most often surprise a business, because they are large and fixed. Put every tax payment date in your 13-week forecast alongside payroll and rent, so the cash is set aside before the date arrives.

If a bill will not fit, contact HMRC before you miss it. If you are struggling to make payments to HMRC, you can ring them on 0300 200 3835 to discuss your payment options. Our guide to HMRC Time to Pay covers how a payment arrangement works. A proposal made early, with a forecast showing when you can pay, is a much stronger position than a bill that has already gone unpaid.

When there is still a gap: overdraft, invoice finance and the rest

If you have collected faster, trimmed stock and costs, and the forecast still shows a shortfall, borrowing is a legitimate tool. The principle is to match the finance to the cause of the gap. A temporary wait for customer payments is a different problem from a permanent need for more working capital.

Speak to your bank as soon as you learn of the shortfall. Do not wait until the account is already overdrawn. A lender is far more comfortable extending credit when it can see a forecast showing how the money will come back.

Option	What it is	Where it fits
Overdraft or increased loan	Extra credit from your bank.	A short, predictable gap, when your bank will provide it.
Invoice finance or debt factoring	You sell or borrow against unpaid invoices. A provider advances a large percentage of the invoice value. With factoring you receive less than the full invoice, but collection can become easier.	Slow-paying customers, and a business that is growing faster than its cash.
Asset finance	You hire or acquire assets and repay their value in agreed instalments.	Equipment or vehicles, without a large cash outlay.
Sale and leaseback	You sell assets such as machinery or equipment and lease them back.	Raising cash from assets you already own and still need.
Line of credit	A set amount to draw on, with interest only on what you use.	Irregular, unpredictable gaps.
Merchant cash advance	A lump sum repaid as a percentage of your future card sales.	Businesses with high card turnover. Check the full cost carefully.
Short-term business loan	Borrowing for a few months or slightly longer, usually unsecured.	A defined, temporary gap.

Some credit options are relatively expensive and unsuited to long-term borrowing, while others lack the repayment flexibility you will need. Costs differ by provider and facility, so ask for the all-in cost in writing, including fees as well as the headline rate, and compare on that basis.

Invoice finance deserves a closer look because it addresses late payment directly. It does reduce what you receive, and that is the honest trade. In return you get cash at the point of invoicing rather than 60 or 90 days later. Whether that is worth the cost depends on your margins and how long your customers take to pay. Our guide to invoice finance in the UK sets out the costs and who it suits, and the invoice finance calculator lets you test the figures against your own ledger.

Cash flow management: a month's plan

• Week 1. Create a cash flow forecast for 13 weeks. List every overdue invoice and chase each one by phone.
• Week 2. Rewrite your payment terms and put late payment interest and fees in them. Start invoicing on the day of delivery.
• Week 3. Review stock, subscriptions and supplier terms. Ask your largest suppliers about longer terms, and sell any assets you no longer use.
• Week 4. Compare the forecast with actual figures. If a gap remains, talk to your bank or a broker while the numbers still look healthy.

Frequently Asked Questions

What are the best ways to increase my cash flow?

The ones that cost nothing come first: invoice on the day, shorten and write down payment terms, chase on day one, and take deposits. After that, release cash from excess stock and unused assets, negotiate longer supplier terms, and build a 13-week forecast. Borrowing comes last, for any gap that remains.

Can a profitable business have cash flow problems?

Yes. Profit is what remains after costs. Cash flow is the timing of money in and out. A profitable business that waits 60 days for payment while paying staff and suppliers sooner can run out of cash and be unable to meet its obligations. Growth can make it worse, because each sale must be funded before the customer pays.

When is a commercial invoice legally late?

If you agreed a payment date, that date applies. It must usually be within 60 days for business transactions, or 30 days for public authorities. If no date was agreed, the payment is late 30 days after the customer receives the invoice or you deliver the goods or service, whichever is later.

Can I charge interest on a late invoice?

Yes. You can claim interest and debt recovery costs if another business is late paying you for goods or a service. The rate and fixed sums are set out in the legislation, so check the current figures on GOV.UK. Stating that you will claim them in your terms makes them easier to enforce.

How much cash should I keep in reserve?

At the least, enough to cover all your costs for a month, and ideally longer. A move from one month to two or three months of available cash is a practical target.

What can I do if a large customer will not pay?

Chase in writing, remind them that you can charge interest or stop supply, and consider your costs before escalating. If a larger business has ignored you, the Small Business Commissioner can review the complaint and help you pursue it.

Deplexifi arranges invoice finance and working capital facilities for UK limited companies, and the quickest way to see whether it fits is to put your debtor ledger and 13-week forecast side by side.

Borrowing to cover a gap before fixing invoicing, payment terms and chasing: you pay a lender for a problem you could remove for free.

Nothing here is regulated financial advice. Deplexifi arranges commercial finance for businesses — this article describes general lending practice and the published position of the sources listed below, not a recommendation for any individual business.