How to Handle Additional Work After a Quote Is Accepted

By Boksit Editorial Team · Last updated: 28 August 2026

Almost every job of any length changes at some point. A wall opens up and the pipework is not where anyone expected, the customer asks for a second socket while you are already chasing the wall, or a supplier discontinues the item you priced six weeks ago. None of that is a failure of quoting — it is simply what happens once work starts.

The problem is rarely the extra work itself. It is the gap between doing the work and agreeing it. This guide sets out a straightforward way of dealing with changes after a quote has been accepted, so the final bill is never the first time the customer hears about the cost.

Why scope changes happen

Scope changes usually fall into a few recognisable groups, and it helps to name which one you are dealing with before you speak to the customer.

• Hidden conditions: rot, damp, old wiring, non-standard construction or anything only visible once work has started.
• Customer-requested changes: additions, upgrades or a change of mind about finishes.
• Third-party requirements: something a building inspector, principal contractor, landlord or manufacturer requires.
• Availability changes: materials that are out of stock, discontinued, or that have moved price since the quote.
• Sequencing changes: another trade running late, forcing extra visits or standing time.

Why a verbal agreement can create a dispute

A quick conversation on site feels efficient, and often both people genuinely believe they agreed the same thing. Weeks later, memories differ about whether a figure was a rough indication or a fixed price, whether it included materials, or whether it replaced part of the original scope rather than adding to it.

Disputes over extra work rarely come from dishonesty. They come from two reasonable people remembering an unwritten conversation differently. A short written record removes almost all of that risk, and it protects the customer as much as the contractor.

You do not need formal contract language. A few clear sentences, a price, and a reply saying "yes, go ahead" is far stronger than the best-intentioned handshake.

Step one: document the change

Write down what has changed while it is fresh, before you price it. A useful record answers four questions:

1. What was originally quoted for this part of the job?
2. What has changed, and why?
3. What extra work is now needed, described in plain language?
4. What happens if it is not done — a delay, a compliance issue, or simply an aspect the customer wanted?

Step two: price the extra work properly

Extra work is often priced too quickly and too cheaply, because it is priced verbally, in the middle of a working day, under mild pressure to keep things moving. Treat it as a small quote of its own.

• Labour: realistic hours, including any repeat visit, set-up and clearing up.
• Materials: current supplier prices, not the prices in the original quote.
• Disruption: time lost to reworking a sequence, standing time or additional access equipment.
• Waste and disposal, where the change creates more of it.
• VAT, if you are VAT registered, and any deduction arrangements that apply to the contract.

Step three: get approval before continuing where possible

Where it is safe and practical, get agreement before the extra work is carried out. That order matters: approval before the work is a decision the customer makes, approval afterwards is a bill they are asked to accept.

There are genuine exceptions. Emergency making-safe, isolating a leak or dealing with an immediate hazard cannot wait for an email. In those cases, do the safe thing, then document what you did and why as soon as you can.

If the customer needs time to decide, say clearly what happens to the programme while they think about it. "I can hold the plastering until Thursday, after that it moves to the following week" is honest, not pushy.

Step four: record how approval was given

Approval arrives in different ways: an online approval, a reply to an email, a text message, or a conversation on site. All of them can be valid — what matters is that the record shows what was approved, by whom, and when.

If approval was given verbally, follow it up in writing the same day: "Confirming the extra work we discussed this morning — additional first-fix to the utility room, £340 plus VAT, agreed on site." That single message converts a memory into a record.

Step five: update the project totals

Once extra work is approved, the job is no longer worth what the original quote said. Keeping a revised total visible — original value, approved extras, revised total, payments received, outstanding balance — prevents the awkward moment at the end where the invoice is larger than the customer's mental figure.

Work that is still pending should never be counted in an approved total. Keeping pending and approved amounts separate is what makes the running figure trustworthy.

Step six: invoice the extra work

You can either invoice extras as you go or roll them into a later invoice or final account. Either works, provided the invoice describes the extra work in the same words used when it was approved. If the approval said "additional first-fix to the utility room", the invoice line should say that too, not "variation 3".

Where a job runs over weeks, invoicing approved extras alongside stage payments keeps the outstanding balance realistic and avoids a large surprise at the end.

How Boksit supports this workflow

Boksit's Additional Works feature is built around the sequence above. You create an Additional Work request against the existing Project, describe and price the change, and send the client a secure link to review it. The client can approve or sign online, and approvals given verbally or by email can be recorded against the same item so the Project stays accurate.

Approved Additional Works feed into revised Project totals and the Project Report, while pending items stay separate until the client responds. Because the request is attached to the Project rather than living in a separate email thread, the history of what was agreed stays with the job.

Frequently asked questions

Should I stop work while waiting for approval of extra work?

Usually you should pause the affected part of the job rather than the whole site. Continue with unaffected work, make anything unsafe safe, and tell the customer plainly what the delay means for the programme.

Is a text message enough to agree extra work?

A text can be a perfectly good record if it states the work and the price and the customer clearly agrees. What matters is that the description and figure are unambiguous and that you keep the message.

Can clients approve Additional Works online in Boksit?

Yes. Boksit can send a secure Additional Work link for the client to review and approve or sign online, and the approval is recorded against the Project.

What if the customer refuses to pay for extras they agreed verbally?

You are relying on evidence at that point: notes, photographs, messages and any written follow-up. This is exactly why confirming verbal agreements in writing the same day is worth the two minutes it takes.