There are
1,552 mi
from Harlingen, TX to Oceanside, CA
That's the driving distance. It would take 1 day 2 hours to go from Harlingen, Texas to Oceanside, California.
The flight distance (direct flight from Harlingen, TX to Oceanside, CA) is 1,274.01 mi.
1,552 mi = 2,497.70 kms