How do I know whether my address is unincorporated?
Do not go by the mailing address. A mailing address names a post office, and the post office's town is not always the government that covers the lot. Ask the city you think you are in, or the county's planning office; the county-by-county table shows who to ask in four counties.
Does a home-based business need a licence?
Often yes, but a city may not charge a fee for a resident's home-based business unless its offsite impact materially exceeds the home's alone, and a county is under the same limit. Excite Tax's reading: no fee is not the same as no licence, so ask the city whether it still wants the application.
Does a teenager's occasional business need a licence?
Excite Tax books it to a Taxes and licenses expense account. For a sole proprietor that total lands on Schedule C, line 23, which covers licences and regulatory fees paid each year to state or local governments. More on setting up accounts.
Why did the county assessor write to me after I got a licence?
The legislative body of a municipality may license for the purpose of regulation any business within the limits of the municipality, may regulate that business by ordinance, and may impose fees
Two words in Utah Code 10-1-203 matter. "May" means the statute lets a city or town license businesses; each city's own ordinance decides whether it does, which businesses it covers and what it charges. "Within the limits" means the city's reach stops at its boundary. So the first question is never the county; it is which city's limits the business sits in, and what that city's ordinance says.
What the statute gives a county
the legislative body may by ordinance: (a) provide for the licensing of businesses within the unincorporated areas of the county for the purpose of regulation
A county's licensing power in Utah Code 17-64-505 reaches only the unincorporated areas: land that is not inside any city or town. Excite Tax's plain reading is that a business inside a city deals with the city, and a business outside every city deals with the county. Older guides cite this rule by its previous number; it was formerly Utah Code 17-53-216 until the county code was recodified.
Who licenses where, county by county
Who issues the licence, by where the business sits. Excite Tax took each row from the county's or district's own page.
Weber County itself; Excite Tax has not yet read a current county page that states the rule, so ask the county planning office.
Three owners doing the same work show how it plays out. A wedding photographer working from a home in Magna applies to the Municipal Services District, not Salt Lake County. One working from Lehi applies to Lehi, because a city licenses within its own limits. One working from Veyo applies to Washington County, because Veyo is unincorporated.
Salt Lake County is the one that surprises people. Its unincorporated areas and the district's member communities all license through the district, which says a licence is valid for 12 months. Utah County's licences run from July 1 to June 30 whatever month they were issued, so a licence bought in May is due again in weeks.
Record the fee as a Taxes and licenses expense; for a sole proprietor it rolls up to Schedule C, line 23. Keep the receipt with the licence.
Put the renewal date on the close calendar. Utah County renews every July; the Salt Lake district's licence lasts 12 months. A monthly close is a good place to catch it.