October 13, 2026 · Mitt Patel · 6 min read
You're standing in a half-finished kitchen on a Tuesday, and the homeowner asks for a bigger window over the sink. You say sure, no problem, and move on with your day. Three weeks later the job is done, the invoice goes out for the original contract amount, and the extra $1,400 in glass and labor is just gone.
Why this keeps happening
Change orders happen in conversation, not on paper. The homeowner asks for something, you say yes because you want to keep the job moving, and everyone moves on. Nobody stops to write it down or figure out what it costs.
The work still gets done. The materials still get bought. The labor still gets paid. But because there's no paper trail, it never gets added to what the customer owes. By the time you're writing the final invoice, you've forgotten half of what changed, and the stuff you do remember feels awkward to bring up after the fact.
This is how profitable jobs turn into break-even jobs. You priced the job at a certain margin. Every unbilled change order eats into that margin, one small amount at a time, until you look at your numbers at the end of the month and can't figure out why a job that should have made money barely did.
It also wrecks your ability to make decisions. If you don't know which jobs are actually profitable, you can't tell which types of work to chase more of and which to avoid. You end up pricing your next job the same way, and the same thing happens again.
A worked example
Say you're remodeling a kitchen for $18,000. Partway through, the homeowner decides she wants a bigger window over the sink instead of the one in the original plan. That means a new rough opening, a different window unit, and an extra day of labor for your crew.
The extra material runs $700. The extra labor, figure a full day for one person, runs $700 more. That's $1,400 in extra cost that wasn't in your original bid.
If you never write this down, the job still finishes, and you still invoice $18,000, because that's the number in your head and in the original contract. But your actual costs on the job are $1,400 higher than planned. That $1,400 comes straight out of your profit.
If instead you write up the change the day it happens, price it at $1,400 (or more, if you want to mark it up like the rest of the job), and add it to the job's contract value, your new contract total is $19,400. Your next invoice reflects that. The homeowner isn't surprised, because she agreed to the window change in person. You get paid for the actual work you did.
How to set it up
- Keep a change order log for every job. This can be a simple paper pad in the truck, a notes app, or a field inside QuickBooks Online if you're using it to track jobs. The format matters less than the habit.
- Write it down the same day. The moment a customer asks for something different, write the date, what changed, and a rough idea of the extra cost. Don't wait until the end of the week when details blur together.
- Price it before you forget what it took. Once you know the material cost and the labor hours, turn the rough note into an actual number. Do this within a day or two, while the job is fresh.
- Get a signature or a text confirmation. A one-line text saying "confirming you want the larger window, additional cost $1,400" and a reply of "yes" is enough. It doesn't need to be a formal contract, but it needs to exist somewhere.
- Add the change order to the job's contract value. Your job isn't an $18,000 job anymore. It's a $19,400 job. Update that number in whatever system you use to track job costs, so your profit calculation at the end reflects reality.
- Bill it with the next invoice, not at the end. Don't let three or four change orders pile up for months. If you invoice progress payments, add the change order to the next one. If you invoice at completion, make sure every logged change order is listed as its own line item.
What undoes this
- Treating verbal agreement as enough. A homeowner nodding on site is not the same as a written record you can point to later. Memory fades, and so does goodwill, if the final invoice has a surprise on it.
- Batching change orders for the final invoice. Waiting until the job wraps up means you're reconstructing conversations from weeks ago. Details get missed, and amounts get rounded down because you're not sure anymore.
- Not pricing labor time separately. It's easy to remember the extra window unit cost $700. It's much easier to forget the extra day your crew spent installing it. Both need to go in the log.
- Letting "small" changes slide. A $150 upgrade here and a $200 change there don't feel worth the paperwork in the moment. Over a job, or over a year of jobs, those small changes add up to real money.
- Forgetting to update the job's contract value. Even if you bill the change order, if you don't update the total contract amount in your records, your profit reports for that job will still be wrong.
Monthly checklist
- Pull the change order log for every open job and confirm each entry has a price attached.
- Check that every priced change order has been added to an invoice.
- Confirm the job's contract value in your records matches the original contract plus all approved changes.
- Review any job where actual costs are running close to or above contract value, and check whether unbilled change orders are the reason.
Common questions
What if the customer refuses to pay for a change they asked for?
This is exactly why you want something in writing, even if it's just a text message, before the work happens. A clear record of what was asked for and what it would cost protects you if there's a disagreement later.
Do small changes really need their own paperwork?
Yes, especially if you do a lot of jobs. A $150 change that gets skipped on ten jobs a year is about $1,500 in lost margin, and it's invisible until you go looking for it.
Should change orders be billed separately or folded into the next regular invoice?
Either works, as long as it's clear to the customer what they're paying for and when. The key is billing it close to when the work happened, not saving it all for the final invoice.
How does this connect to job costing overall?
Change orders are one of the most common reasons a job's actual costs drift from its original budget. If you're tracking job profitability at all, unbilled change orders are often the first place to look when a job underperforms.
Setting up a change order system that actually gets used, and keeping job contract values current as changes come in, is exactly the kind of recurring work North Hudson Bookkeeping handles for contractors and remodelers in North Jersey. The first call is free, and it's a good place to start if you're not sure your current jobs are billing for everything they should.
