Visa inquiry flying into SGN

Hello, 

I have used your services in the past and am  looking forward to using them again for my upcoming trip.  I have a  question, first: I am flying into SGN on Feb 18th at 5:50 am.  I will  leave that day at 10:10 am for Laos (VTE).  Two weeks later I will  return to Vietnam.  I know I will need a visa to enter Vietnam.  Do I  need a visa for the time I will be in the airport on the 18th or can I  have the start date for the visa be when I return from Vietnam from  Laos?

Thank you.