The time it takes for a letter to arrive depends on the type of mail, the distance between the sender and recipient, and the time of year.
Type of mail
First-Class Mail: Usually takes 1–5 business days to arrive
Priority Mail: Usually takes 1–3 business days to arrive
USPS Ground Advantage: Usually takes 2–5 business days to arrive
Distance
Local delivery: Usually arrives the next day
Within 400–600 miles: Usually arrives in two days
Coast-to-coast: Usually arrives in three days
Time of year
Holiday season: Mail may be delayed due to backlogs and system malfunctions
Other factors that can affect delivery time include: The size of the mail, Possible breakdowns, and System malfunctions.
You can check the USPS website for local mail delivery times in your area