How do I pay the visa stamping fee at a Vietnam airport?

Dear Paul,
Thank you for contacting us.

Stamping fee for a single entry one month visa at Vietnam airport is 25 USD ( price per person).

Please let us know if you have any further questions.

Dear Steve Landvatter,
The stamping fee for a  single entry 1-month visa is 25 USD, in cash and no credit cards accepted. We are not sure if they accept other currencies, so we advise that you prepare some US dollars (Or VND) before you travel.

Please let us know if you have any further questions.

Dear Ashley Gillies

That is fine, the stamping fee can be paid by VND instead of USD. Please be advised that you prepare some VND before you go. 

Dear Carol Prichard

The stamping fee must be paid by USD or VND, so please be advised that you prepare some USD or VND before you go in this case.
Please do not hesitate to let us know if you have any other questions.

Dear Jonathan Berg

The stamping fee can be paid by USD or Vietnam dong, so you can prepare either USD or VND before you go.
Best regards, 

Dear Yugi Gao,
Thank you for contacting us.

We would like to clarify as follows:

1. Stamping fee for a single entry 1-month visa at Vietnam airport is 25  USD ( per person), payable in cash and no credit cards accepted.

2. The on arrival form is available at Vietnam airport, however, we advise that you fill it out before you travel to save time at the airport.

3. It is required to complete 01 On arrival form for each applicant. Please complete the forms before you travel.