Can I leave Vietnam for a day and come back to get another 45 days visa free?

You may be allowed back in, but there is no promise. Border officers decide on each entry, and repeated visa-free entries raise questions about the purpose of your stay.

Some travelers do leave and re-enter and report no problem, but others are asked about onward plans or told to apply for a visa. Rules for repeat entries have changed in the past, so look at the current text on xuatnhapcanh.gov.vn and the Vietnam visa exemption guide.

If you plan a long stay, apply for an e-visa before you fly. A multiple-entry e-visa lets you leave and return within its validity, up to 90 days, without relying on exemption rules at the border.

Keep return or onward tickets, hotel bookings and proof of funds ready if you do cross the border. Airlines use the same questions at check-in.