Can a general contractor charge more than the original written estimate without a signed change order?

No, a reputable general contractor should not charge more than the original written estimate without a signed change order. Here's what you should know:

Your Protection: A written estimate is essentially a binding agreement on price. If work scope changes or unexpected issues arise (like hidden damage during demolition), the contractor should notify you *before* proceeding and get your written approval for any price increases. This is called a change order, and it protects both you and the contractor.

Red Flags: If a contractor bills you significantly over the estimate without prior written approval, that's a major problem. Legitimate reasons for overages might include discovering structural damage, code violations, or materials price increases — but these should be communicated upfront, not as a surprise bill.

What to Do: Always require change orders in writing before work continues on any additions or changes. Keep all estimates, invoices, and change orders together. If you're hit with unexpected charges, review your contract terms, communicate with the contractor immediately, and consider filing a complaint with your state's licensing board if the contractor refuses to justify the charges or won't negotiate.

Pro Tip: When getting estimates, ask contractors to spell out what's included, what's excluded, and under what circumstances they'd issue change orders. This prevents misunderstandings later.