If my US visa is valid till March 15th 2019, then can I enter into US on 13th Mar 2019? Can CBP (Customs & Border Protection) at the US port of arrival refuse entry based on validity of visa?
They can refuse you but your visa is valid and if you're a genuine visitor you should be fine. You will tell tho CBP officer how long you're staying and they will give you a stamp with the last day you're allowed to leave. If you stay over the date they give you you'll be an overstayer.
The visa expiration date is shown on the visa along with the visa issuance date. The time between visa issuance and expiration date is called your visa validity. The visa validity is the length of time you are permitted to travel to a port-of-entry in the United States.
Upon arriving at a port of entry, the CBP official will determine the length of your visit.
The admitted-until date or D/S notation, shown on your admission stamp or paper Form I-94 is the official record of your authorized length of stay in the United States. You cannot use the visa expiration date in determining or referring to your permitted length of stay in the United States.
3+1 However that said people entering on the dying days of their visa get extra scrutiny. Mar 6, 2019 at 13:07
Nothing here suggests that this is a visitor visa. If it is not, then of course the part of this answer about being a genuine visitor does not apply.– phoogMar 6, 2019 at 14:28
@phoog true, but ill leave it in incase for now Mar 6, 2019 at 15:21
Anyway the rest of the answer is perfectly applicable to any nonimmigrant.– phoogMar 6, 2019 at 22:49