Change Order Billing: Getting Paid for Extra Work

Every contractor has a version of the same story. The owner's rep asks for an extra run of duct, a relocated panel or a weekend shift to catch the schedule. The crew does it. The paperwork trails behind, the change order sits unsigned, and three months later the extra work is the one line on the job nobody has paid for.

To get paid for a change order, treat it as its own receivable from the day the work is requested. Get the scope and price approved in writing before or as the work starts, bill it as its own line or invoice the month it is approved, track pending changes on a separate log, and follow up on the same cadence as your base billing. Most unpaid change order money is lost to missing paperwork and missed follow-up, not to customers who refuse to pay.

The story is common because construction payment is already strained. Rabbet's 2024 Construction Payments Report found that 82% of contractors wait more than 30 days to get paid, up from 49% two years earlier. Credit Pulse's 2026 DSO benchmarks put a typical construction company at 72 days to collect on net 30 terms. And in Arcadis's 2025 Construction Disputes Report, owner-directed changes ranked as the third most common cause of construction disputes in North America, up from fourth the year before.

Change orders are where slow pay turns into no pay. This guide covers what to capture before the work starts, how to bill a change order so it clears approval, how to track the ones still pending, and what to say when the money does not show up.

Why Do Change Orders Get Paid So Slowly?

Change orders get paid slowly because they break the normal billing path. Base contract work is priced, scheduled and approved before the job starts. A change order is priced after the fact, approved by someone who may not control the budget, and billed by an office that often hears about it last.

The work happens before the paperwork

Field crews respond to what the site needs that day. A superintendent says yes to a verbal request, the work gets done, and the written change order follows days or weeks later, if it follows at all. By then the owner's memory of what was agreed is softer than yours.

Pending is not approved

A change order that has been submitted but not signed is not a receivable yet. In most workflows it cannot go on a pay application, so it never shows up in your aging report, so nobody chases it. That is how a job can look fully billed while real money is missing.

It gets buried in the pay application

When an approved change is added to a large pay application, a question about that one change can hold up the whole draw. The GC's project manager queries a single line and the entire application goes back for revision. We cover that wider progress billing friction in receivable challenges in construction and contracting.

Nobody owns the follow-up

Project managers own the scope conversation. The office owns the invoice. Change orders fall between the two, and each side assumes the other is chasing.

What Should a Change Order Include Before You Bill It?

A change order is ready to bill when someone with authority to approve it could read it cold, a month later, and agree it is correct. That means the document has to carry its own evidence.

A billable change order should include:

• A reference to the original contract and a change order number, so it can be matched to the job and the schedule of values.

• A plain description of the added or changed work, where it happened and why it was requested.

• Who requested it, by name and title, and the date of the request.

• The price, broken out as labor, materials, equipment and markup, or the time and materials rates that will apply.

• Any schedule impact, stated in days, so time and money are settled together.

• Backup: photos, delivery tickets, daily reports or signed time and materials tickets.

• A signature line for someone with authority to approve it, and the date it was signed.

The signature is the line between a receivable and a hope. Arcadis's survey respondents ranked contract and specification reviews and good communication as the two most effective ways to avoid disputes, and a signed change order is both on one page. If a customer will not sign before the work starts, get written approval by email at a minimum and attach it to the change order file.

Your contract usually sets out who can approve a change and in what form. Build your change order template around those steps so the office never has to guess, and so the person signing sees exactly what they are agreeing to.

How Should You Bill a Change Order?

Bill an approved change order as soon as it is signed, in the format your customer's approval process expects. For most contractors that means one of four routes.

Bill it the month it is approved

Do not hold an approved change for the next big draw or for closeout. Every month it waits is a month your cash is funding the owner's decision.

Keep change work visible as its own line

Show each change order number and amount on its own line, with a running total of approved changes against the original contract value. It makes the pay application easier to review, and it makes a question about one change less likely to stall the base billing.

Ask for the purchase order number up front

Many commercial customers cannot pay an invoice their system cannot match. If the change needs a new or revised purchase order, ask for it when the change is approved, not when the invoice bounces back.

How Do You Track Pending Change Orders in Your A/R?

Track pending change orders on a log that sits next to your aging report, because the aging report cannot see money that has not been invoiced yet.

Keep one change order log per job

The columns that earn their place: change order number, description, date requested, date submitted, amount, status (requested, submitted, approved, billed, paid or disputed), who owes the next step, and the next follow-up date.

Age pending changes from the date the work was done

An unsigned change that is 60 days past the work is as dangerous as a 60-day invoice, even though it never appears in the aging. Review the log in the same weekly meeting as the aging report, sorted by days since the work was done.

Reconcile before closeout

Before the final billing, compare the log to what has been billed and paid. Unresolved changes get much harder to collect once the crew has demobilized and the owner's attention has moved to the next project. The same is true of the holdback at the end of the job, which we cover in retainage and construction DSO.

If your books run on Sage 100 Contractor, our guide to its aging report shows how to get the invoiced side of this picture out of the system on a schedule.

What Should Change Order Follow-Up Sound Like?

Change order follow-up should sound like a project update, not a collections call. The goal is the next signature or the next payment, while keeping the relationship you need for the next bid.

When the change order is unsigned

"Hi Dana, this is Sam from Northside Mechanical. We finished the added duct run on level three on the 12th. Change order 14 went over on the 15th for $8,450 with photos and the delivery tickets. Can you sign it this week, or tell me what needs to change so it can go on the October pay app?"

When it is approved but not paid

"Hi, I am calling about invoice 2291 for change order 14 on the Elm Street job, approved on the 20th for $8,450. Can you confirm it is in your system and which payment run it is scheduled for? If you need a purchase order number, I can send it today."

When the amount is disputed

"Thanks for flagging that. Which part of the change do you disagree with: the scope, the quantities or the rates? If we can agree on the undisputed part, can you release that portion now while we sort out the rest?"

Splitting the undisputed amount from the disputed one keeps cash moving while the harder conversation happens. For a wider set of responses, see our guide to late payment excuses and what to say to each one.

When Is a Change Order Dispute No Longer a Collections Problem?

A change order dispute stops being a collections problem when the question is about scope or price rather than timing. At that point more reminders will not help; the right people need to talk.

• A timing question ("it is in the queue", "we need a PO"): keep following up on your normal cadence.

• A documentation question ("we cannot find the backup"): resend the file the same day and confirm it arrived.

• A scope or price question ("we never agreed to that"): pause the reminders and hand it to your project manager and an owner of the business, with the full file.

• Silence after several contacts on an approved, undisputed change: escalate internally and decide the next step. Our guide on when to escalate an invoice walks through that decision.

Where Does Automation Fit in Change Order Collections?

Automation fits the repetitive half of change order collections: confirming receipt, checking approval status, asking for purchase order numbers and following up on approved changes once they are billed. The judgment half, negotiating scope and price, stays with your project managers.

Abivo's AI employee, Kate, works from the aging report or accounting data you already have. Once a change order is invoiced, Kate calls, texts and emails the right contact on a steady cadence, logs what each customer said and hands anything that sounds like a scope dispute to your team with the conversation attached. You can read how that works step by step in how an AI agent calls customers about overdue invoices, see a real trades example in the OFS Group case study, or listen to a sample call.

For the broader buying picture, see our guide to collections software for construction contractors, and for how we work with the sector, construction, engineering and field services.

Practical Takeaways for Contractors

• Treat every change order as a receivable from the day the work is requested.

• Get written approval before or as the work starts; an email beats nothing.

• Put the price, the backup and the schedule impact on the change order itself.

• Bill approved changes the month they are approved, each on its own line.

• Keep a change order log and review it with the aging report every week.

• Split disputed amounts from undisputed ones and ask for the undisputed part now.

• Hand scope and price disputes to people; automate the reminders and status checks.

Frequently Asked Questions

What is change order billing?

Change order billing is invoicing a customer for work added to or changed from the original contract scope. Once the change order is approved, it is billed either on a separate invoice or as a new line on the schedule of values in a progress billing application.

Can you bill a change order before it is signed?

Most customers will not pay an unsigned change order, and many pay application workflows reject one. Bill once you have written approval, and chase the signature as hard as you would chase a payment.

How long should it take to get paid on a change order?

Once it is approved and invoiced, about as long as the rest of your billing on that job. The real delay usually sits before the invoice, in the time it takes to price, submit and sign the change. Track that time on your change order log.

Should change orders go on the pay application or a separate invoice?

Follow what your customer's process expects. Larger progress-billed jobs usually add approved changes to the schedule of values, while small jobs and service work often bill changes on a separate invoice. Either way, show each change as its own line.

What if the customer says the change was never approved?

Send the file: the request, the date, who asked, the photos and any written approval. If the disagreement is about scope or price, move it out of collections and into a meeting between your project manager and theirs.

Want every approved change order and progress bill followed up every week without adding staff? Get Started.