COVID Test for Return to USA

There's nothing like that set up. Belgium is not open for tourism currently.
Make sure to visit Ghent and Dinant if you go.

If you still need a test winter 2021-2022, the locals wherever you are will be able to tell you where to get a test or you should be able to find the information on the American Embassy in Belgium website. You should also check to see if tests are available at the departure airport. Check the airport website. You need only a quick antigen test to return to the US, not a longer PCR. I was able to get an antigen test at a local pharmacy in France and again at the international airport when I flew back to the States a couple of months ago.

Given the progress with vaccination in the US, I would think ( hope?) that by Dec a vaccinated US citizen would not need a test to return home.

I think the bigger issue is will Belgium be letting tourists in.

Joe32F, but what about all the variants and the fact that the vaccine doesn't make you immune from contracting and spreading the virus? Belgium? Maybe 2024.

Check your airline's website as you get closeer to your date of travel. Many have information as to where to get a test.

Hopefully, by next winter things will have changed for the better.

Check with your hotel. I know it's not Belgium but we traveled to Mexico (Los Cabos - big tourism area) a couple of weeks ago and most of the large American hotels were arranging for the necessary COVID tests to get people back home. Some were free while ours had a nominal charge. The local hospitals also had walk in service. Once the EU starts opening up they would be wise to look at the Mexico model because it worked well.