How the port rule plays out on run day
E-visa holders come back over Lao Bao in one of two ways, and both depend on the entry port field.
First, the multiple-entry e-visa. If you hold the 50 USD multiple-entry version and it lists Lao Bao as the entry port, re-entry on run day is a clean stamp. You exit, spend twenty minutes on the Laos side, walk back, the officer scans your e-visa, the port matches, and you get a fresh entry mark inside the same 90-day window. This is the smoothest rhythm for anyone running regularly, and it only works when the port was right from the start.
Second, the new e-visa filed from the border. Single-entry holders, and anyone whose multiple-entry visa lists a different gate, cannot legally step back into Vietnam through Lao Bao on that document. The standard move is to apply for a fresh e-visa while on the Laos side, with an entry date of today and Lao Bao as the entry port, then cross back once the approval lands. Rush processing can turn that around in a few hours, which is why same-day runs are still possible for single-entry travelers. This is also the moment of maximum risk: a rushed application with the wrong port burns the fee and the day together, because there is no time left to file again before the border closes.
Either way, the entry port on the document you actually use must say Lao Bao. The officer does not care what the old visa said, only what the current one declares. People who apply for the fresh e-visa from home a week early, then run on the day it arrives, need to double check one thing before pickup: which port did you type in. In our experience across hundreds of Lao Bao runs, that check takes ten seconds and prevents almost every border failure we see.
The full border sequence, exit stamp to re-entry, is written out step by step on our Lao Bao visa run guide, and the how to do a visa run page covers what to carry.