How to Record Part-Payments on Trade Invoices

When a customer pays only part of a trade invoice, keep the original invoice intact and record the amount received against it. The balance still due is the invoice total minus all payments correctly allocated to that invoice.

For example, if you invoice £2,400 and receive £1,000, the invoice is not paid and its value should not be changed to £1,000. It is part-paid, with £1,400 still outstanding. If the original due date passes before the rest arrives, that unpaid balance needs to remain visible as overdue money.

This sounds straightforward when there is one customer and one job. It becomes much easier to get wrong when you have several completed projects, similar payment amounts and bank transfers carrying unhelpful references such as “work” or a surname.

What does part-paid mean on an invoice?

A part-paid invoice is an invoice against which some money has been received, but less than the full amount due has been settled.

The basic calculation is:

Outstanding balance = invoice total − payments allocated to the invoice

If the invoice total is £2,400 and the customer has made two payments of £1,000 and £800, the calculation is:

£2,400 − £1,000 − £800 = £600 outstanding

The invoice remains part-paid until the final £600 clears, unless the amount due is formally changed for a genuine reason such as an agreed price reduction or credit.

A worked example of a part-paid trade invoice

Imagine an electrician completes a consumer-unit replacement and associated testing. The final invoice is £2,400, due on 14 June.

The important point is that every receipt forms part of one clear payment history. At any stage, the electrician can explain what was invoiced, what arrived and what remains unpaid.

How to record a part-payment correctly

1. Confirm which invoice the customer intended to pay

Do not allocate money based only on the customer’s name. A regular customer, landlord or main contractor may have several open invoices.

Compare the bank or card receipt with:

• the invoice reference supplied to the customer;
• the amount received;
• the relevant customer and site;
• any payment message or remittance advice;
• recent conversations about the job.

If the allocation is unclear, ask the customer to confirm it in writing. Guessing can make one invoice look paid while another appears overdue incorrectly.

2. Leave the original invoice value unchanged

A payment does not alter what you charged. It reduces what the customer still owes.

Do not edit a £2,400 invoice down to £1,000 just because £1,000 has arrived. That removes the clearest record of the original sale and can create confusion for both the customer and your accounts.

Likewise, do not normally cancel the first invoice and raise another one for the remaining balance. The useful record is one original invoice with each payment shown against it.

If the agreed price itself has genuinely changed, that is a different issue. Record the commercial reason properly and use the appropriate accounting document rather than disguising a reduction as a payment.

3. Record the amount, date, method and reference

For each receipt, record:

• the date the payment was received;
• the amount;
• the payment method, such as bank transfer or card;
• the bank reference, card reference or customer note;
• the invoice to which it has been allocated.

This gives you a payment trail instead of a single tick saying “paid”. It is especially useful if a customer later says they have settled the full amount.

4. Recalculate the remaining balance

After recording the payment, check the amount still due. Do not rely on mental arithmetic when an invoice has several instalments, a deposit or similarly sized payments.

For a £7,500 landscaping invoice with receipts of £2,500, £1,500 and £2,000:

£7,500 − £2,500 − £1,500 − £2,000 = £1,500 still due

The customer may have paid £6,000 in total, but the job has not produced all of the expected cash.

5. Keep the original due date visible

A part-payment does not automatically replace the due date on the invoice. If the customer pays £500 towards a £1,500 invoice on its due date, the remaining £1,000 does not silently receive another 14 or 30 days.

You can agree a revised date or payment arrangement if that is commercially sensible. Record the agreement clearly, including the amounts and dates promised. Without a new agreement, manage the remaining balance against the original terms.

6. Issue a receipt without marking the whole invoice as paid

A receipt should confirm the amount actually received. It should not suggest that the full invoice has been settled when a balance remains.

A useful payment acknowledgement might state:

Payment of £1,000 received on 10 June against invoice INV-1048. Remaining balance: £1,400.

This confirms the customer’s payment while keeping the next action clear.

Part-payment is not the same as staged invoicing

There is an important difference between an unplanned part-payment and an agreed payment schedule.

With staged invoicing, a builder might agree separate deposit, pre-start and completion stages before work begins. Each stage can be invoiced at the agreed trigger.

With a part-payment, the business has usually raised an invoice for a specific amount and the customer has paid less than that amount. The remaining balance still belongs to the same invoice.

If customers regularly ask to split large bills after completion, consider whether the commercial structure should have been agreed earlier. Deposits and stage payments can reduce the amount left exposed at the end of the job. They should not be invented retrospectively to hide a late or incomplete payment.

How to handle a payment covering more than one invoice

A customer may transfer one amount intended to settle several invoices. For example, a property manager pays £3,000 against three plumbing invoices worth £800, £1,200 and £1,500.

Do not mark all three as paid: the total invoiced is £3,500, so £500 remains outstanding somewhere.

Ask for remittance details or written allocation. If the customer confirms that invoices of £800 and £1,200 are paid in full, the remaining £1,000 can be allocated against the £1,500 invoice. That leaves a clear £500 balance on one invoice rather than an unexplained shortage spread across three jobs.

Common part-payment mistakes

Marking the invoice as fully paid too early

This removes the balance from the work list and makes forgotten money more likely. An invoice should only be treated as settled when the full amount has been received or the outstanding amount has been properly resolved.

Looking only at the bank balance

A bank balance shows total cash, not which customer paid which invoice. It may include deposits for future work, tax money or receipts from unrelated jobs.

Payment control requires the bank receipt to be connected to the correct invoice.

Allocating the payment to the wrong project

This can distort the commercial picture for two jobs at once. One project appears to have collected too much while another looks unpaid. Use the invoice reference, customer, project and site information together.

Forgetting to chase the remainder

Receiving some money can create a false sense that the matter is dealt with. A £5,000 invoice with £4,500 received still has a £500 balance that needs an owner, a follow-up date and a resolution.

Treating a disputed deduction as an agreed discount

If a customer withholds £300 because they claim something is incomplete, record the £300 as outstanding while the issue is investigated. Do not silently reduce the invoice unless you actually agree to alter the price and document that decision appropriately.

Why part-payments matter to cash flow

A job can be profitable on paper and still create cash pressure.

Suppose a carpenter invoices £6,000 after completing fitted storage. The direct materials and labour have already cost £3,800. The customer pays £2,000 and promises the rest later.

The business may have made a commercial profit, but it has not collected enough cash to cover the direct outlay. The missing £4,000 could affect merchant payments, wages and the ability to start the next project.

This is why invoice value, profit and cash received should not be treated as the same figure:

• Invoice value is what you have billed.
• Profit considers the income and costs associated with the work.
• Cash received is the money that has actually arrived.

A good job record lets you see all three without confusing them.

A practical weekly part-payment check

Once a week, review every invoice that is not fully paid. For each one, confirm:

1. the original invoice total;
2. all payments received and correctly allocated;
3. the current outstanding balance;
4. whether the due date has passed;
5. whether the customer has promised another payment;
6. the next follow-up date;
7. whether there is a genuine dispute or merely a delay.

Prioritise invoices that are overdue, high in value or connected to customers with several open jobs. This is more reliable than waiting until the bank balance feels low.

Keeping part-payments connected in Tools2Done

Tools2Done lets a trade business keep an invoice connected to the relevant customer and project. Individual customer payments can be recorded with their date, amount, method and reference or notes, creating a payment history rather than replacing the original invoice value.

Invoices can be followed through sent, part-paid, paid and overdue states, while the dashboard surfaces outstanding and overdue invoice values that need attention. Users can also search by invoice reference, customer, project, amount or date.

Customers can open invoices online. Where Stripe customer payments are configured, they can pay by card; otherwise, the business’s bank-transfer details can be shown. A receipt can be sent when a payment is recorded, including automatically when a payment clears the full balance.

Software cannot make a customer settle the remainder. Its job is to stop an incomplete payment being mistaken for a completed one.

Your next step

Choose one part-paid invoice and reconstruct its full history today. Confirm the original total, every receipt, the remaining balance and the next action. If that takes more than a few minutes, introduce a consistent process that ties each payment to the correct customer, invoice and job.