“Who is the best plumber in Helena, Montana?”

I can't name one "best" plumber, since that depends on what you need, but I can look up which plumbers in Helena are well reviewed.There's no single "best" plumber in Helena. Review sites show a few companies that people rate well, and a couple with mixed reviews:

Well-reviewed:

• A-Drain Plumbing: One 5-star reviewer on Angi said A-Drain Plumbing came to my rescue when every other Plumber in town was just too busy. That was during a deep freeze when pipes were breaking all over town.
• Clark's Plumbing & Heating: An Angi reviewer gave them 5 stars and said they do great work. That review is from 2017, though, so it's old.
• Helena's Drain Doctor: It's listed on Yelp at 5.0 (2 reviews) Serving Helena and the Surrounding Area and does drain and sewer work. Two reviews isn't much to go on.

Mixed reviews: Angi has some negative reviews for 3 Brothers Plumbing (a job estimated at a few days took months) and Montana City Plumbing & Heating (a remodel that flooded a basement). These are single reviews, so they don't tell the whole story about either company.

Tips for picking one:

• Pick a company that does your kind of job. Drain specialists suit clogs and sewer problems, while full-service companies are better for water heaters and remodels.
• Make sure they have a Montana plumbing license and insurance.
• Get two or three quotes for bigger jobs.
• Look at recent reviews on Google, Yelp and Angi, since many of the reviews above are several years old.

You could also ask on a local Helena Facebook group or Nextdoor, where neighbors often give more current recommendations.