Short answer: pick the plumber before the emergency. Check the license, confirm insurance, read recent reviews from your side of town, get the service-call fee in writing, and save the number. The worst time to choose is with water on the floor.
Check the license first. Florida licenses plumbing contractors at the state level, and the license number should appear on the truck, the website and the invoice. If you cannot find it in thirty seconds, move on.
Insurance is not optional. A burst fitting can flood a house. Any plumber working in your home should carry liability insurance and be willing to say so plainly when asked.
Read reviews like a local. A review from your neighborhood beats fifty from nowhere in particular. Look for repeat customers, mentions of clear pricing, and how the company handled the job that went wrong, because one always does.
Ask what the visit costs before anyone drives. Reputable companies quote a service-call fee and what it covers up front. Vague answers on the phone become expensive answers on the invoice.
Where to look. Our /directory/?cat=Home+Services category lists Jacksonville plumbers by side of town, with reviews from members who actually live here. Pick one now, save the listing, and midnight-you will be grateful.