Thai AirAsia (TAA) will introduce a second daily flight from Bangkok's Don Mueang airport to Hanoi from Dec 9.
The airline connects Thailand with seven Asean nations including Cambodia, Laos, Myanmar, Vietnam, Malaysia, Indonesia and Singapore on 17 routes totalling 30 flights per day.
Aside from the daily flight to Hanoi, TAA also serves Ho Chi Minh City with three daily flights.
With the introduction of a second daily flight to Hanoi, TAA will outstrip rival budget carrier Nok Air in terms of frequency from Don Mueang to the Vietnamese capital.
Nok Air operates two daily flights to Hanoi on Monday, Wednesday, Friday and Sunday.
TAA has set a promotional one-way fare, inclusive of airport tax, on the Bangkok-Hanoi route at 990 baht, available for booking by Nov 13 for travel from Dec 9 to Oct 28 next year.
Newly-released figures from the Vietnam National Administration of Tourism show the country welcomed 8.07 million international tourists in the first 10 months of this year, up by 25.4% year-on-year.
Nearly all of Vietnam's top markets are in the Asia-Pacific region, with the exception of the US (fifth), and Russia (seventh).
China ranked top in international arrivals to Vietnam in the January-October with 2.22 million (up 55% year-on-year), followed by South Korea with 1.25 million (up 40.1%), Japan with 611,401 (up 10.8%), and Taiwan with 423,401 (up 15.9%).
Thailand was 10th in arrivals to Vietnam in the period with 212,271 (up 30.8%)
Most arrivals to Vietnam came through Hanoi and Ho Chi Minh City.
This year, Vietnam is expected to attract 8.5 million foreign visitors and 60 million domestic travellers, and earn US$16.8 billion in revenue.