The short answer
HighLevel is based in Dallas, Texas. Its website gives the address as 1801 N. Lamar St., Suite 600, Dallas, Texas 75202, and its Terms of Service are governed by Texas law. The company was founded in 2018, its toll-free number is +1 (888) 732-4197, and support runs around the clock, so customers outside Central time are not limited to Dallas office hours.
Addresses HighLevel publishes
The about page and site footer give 1801 N. Lamar St., Suite 600, Dallas, Texas 75202 as the company address. The Terms of Service list a different Dallas address for legal notices: HighLevel LLC, ATTN: Legal Department, 5473 Blair Rd Ste 100, PMB 383313, Dallas, Texas 75231-4227. Formal legal notices belong at that second address. Billing questions go to billing@gohighlevel.com or the toll-free number, option 2, rather than to either street address.
What a Texas base means for customers
The Terms of Service say the laws of the State of Texas govern the terms and any disputes under them. Prices are quoted in US dollars, and HighLevel's sales and use tax FAQ, which covers US customers only, says it collects sales tax on applicable subscription and wallet charges. For US agencies and small businesses, that means a domestic vendor, a contract under Texas law and tax handled on the invoice where your state requires it. This is general information, not legal advice.
Support hours and time zones
HighLevel's support article says help is available 24/7 through live chat with support agents, Zoom support rooms and email tickets from inside the app. The phone line, +1 (888) 732-4197, handles sales, billing and login issues, and international numbers are listed too. New accounts can meet a Trial Experience Team during the 14 day trial, and paying customers get a Success Team for onboarding in the first 90 days, so the Dallas location does not decide when you can get help.
More answers in HighLevel questions. For costs, see GoHighLevel pricing or run the cost calculator.