The consensus among sources found on the internet is that home services are not tipped. But do you tip a locksmith?
No. People like plumbers, electricians, construction workers, and locksmiths are providing professional services, and aren’t relying on tips to make up the majority of their wages (as they do for jobs in the hospitality industry). If the commercial locksmith helps you in a particularly bad or difficult situation (let’s say its a freezing Arizona night…and its Christmas Eve and you want to rekey locks), you may want to give something extra as a sort of acknowledgment of your shared humanity, but generally it’s not necessary.
However, if the locksmith does an extraordinary job or you hired a 24 hour emergency locksmith, perhaps the best way to fully repay them is to leave a review on Yelp and Google that accurately describes the quality of their work and helps to spread the word about their great services to your friends and family. This ensures not just that the locksmith benefits from your comments, but that more and more people will get good locksmith service from dependable companies.