Bamboo Airways will cease all regular flights for two weeks from July 26 to August 7 amid the severe spread of the disease and social distancing measures imposed in major cities, it stated.
Websites of Vietjet and Pacific Airlines on Tuesday showed few or no flights between popular destinations like Hanoi, Ho Chi Minh City and Da Nang.
Most passenger flights between HCMC and Hanoi have been cancelled since July 23 as the capital imposed strict social distancing.
Vietnam Airlines is the only carrier operating on this route with a maximum of two flights a day allowed.
Between June 19 and July 18, the number of flights plunged 84.6 percent to 3,772, according to the Civil Aviation Authority of Vietnam (CAAV).
Vietnam has recorded 105,287 local Covid-19 patients in 62 cities and provinces since the new wave started three months ago.