How to write a change order

A change order is a short written agreement that changes the scope, price or schedule of a signed contract. Done every time, it keeps you paid for extra work and keeps the customer from being surprised by the final bill.

Start in the contract

The CCB's consumer guidance says well-written contracts often include an agreement that changes to the contract happen only through written change orders signed by both the contractor and the homeowner. Put that clause in your contract, and say how hidden conditions (rot, old wiring, anything you could not see when you bid) will be priced. See Oregon residential contract requirements for what the contract itself must include.

What goes on a change order

• Project name, job address and the original contract date
• Change order number and date
• Who asked for the change, and why (owner request, hidden condition, inspector correction)
• What is added or removed, described as clearly as the original scope
• Price impact as line items: materials, labor, subs, permit or plan-revision fees, overhead and profit
• Running contract total: original price, plus or minus earlier change orders, plus this one
• Schedule impact, in days
• When the change is paid (next draw, on completion, or up front)
• Signatures and dates from both parties

Step by step

1. Stop and document. Photograph the condition or note the request before you touch anything.
2. Price it the way you priced the bid: takeoff, labor by task, subs, fees, then overhead and profit. Use the bid calculator and the method in how to price a remodel bid.
3. Write it up with the fields above. Use the same form every time.
4. Get it signed before the work. A verbal "go ahead" is how unpaid extras happen.
5. Check permits. If the change touches permitted work or approved plans, ask the local building department whether a revision or new permit is needed.
6. Update the schedule and the next invoice, then file the signed copy with the contract.

Oregon points to know

• If a residential job started under $2,000 and changes push it over $2,000, the CCB says you must give the owner a written contract within five days (ORS 701.305). Its notices chart says the construction lien notice must be mailed or delivered no later than five working days after you know the price went over. Details and links: contract requirements.
• The CCB says skipping the written contract or required notices may cost you the ability to claim a lien (ORS 87.037). Source: CCB contractor tools.

Habits that prevent change-order fights

• Price changes before you do them, never after.
• Give the customer the running total on every change order, so the final bill matches what they signed.
• Note credits for removed work as clearly as charges for added work.
• Keep change orders numbered in order, with the job file. More in our bidding tips.

Sources: CCB consumer tools, CCB contractor tools and CCB required notices chart, checked Oct 17, 2026.