No statutory cap, but reasonableness is tested twice
Arizona imposes no statutory percentage cap on attorney contingency fees in general personal injury or medical malpractice cases. The fee is set by private agreement between attorney and client, subject to Arizona Rule of Professional Conduct ER 1.5. 33.3%, or one-third, is a commonly used figure.
A genuinely distinctive Arizona rule: fees get a second look
Here's something worth knowing: in In re Swartz, 141 Ariz. 266 (1984), the Arizona Supreme Court held that a contingent fee reasonable when the agreement was signed can still become "clearly excessive" by the end of the case, if the actual work performed and results obtained don't justify it — in that case, a one-third fee for roughly 20–30 hours of work, after a workers' compensation lien consumed most of the recovery. This means your attorney's fee in Arizona isn't locked in purely by the percentage on paper; it can still be reviewed for fairness against what actually happened.
What else comes out before you do
Case costs — expenses the attorney typically advances during litigation, like expert witness fees, filing fees, and the cost of gathering medical records — are generally reimbursed from the settlement. If Medicare, Medicaid, or a private health insurer has an outstanding lien for medical treatment related to the injury, that amount is also repaid before you receive your net share.