The airline group, comprising Vietnam Airlines, Pacific Airlines and VASCO, said higher passenger volumes could lead to longer waiting times for check-in, security screening and immigration procedures, particularly during peak hours.
Passengers are advised to arrive at least two hours before domestic departures and three hours before international flights, while ensuring they have valid travel documents.
For international flights, especially those departing late at night or early in the morning, travellers are encouraged to allow extra time to complete check-in, security and immigration procedures.
To reduce waiting times, the airlines recommend online check-in within 24 hours before departure through the Vietnam Airlines website, mobile app, VNeID, call centre or self-service kiosks at airports.
The group said biometric technology could further speed up check-in, particularly for passengers travelling without checked baggage.
Passengers are also advised to proceed promptly to security screening and, for international flights, immigration after completing check-in to ensure they reach their boarding gates on time.
Vietnam Airlines Group said it plans to operate about 28,300 domestic flights and offer nearly 5.5 million seats through August 16, up 5 per cent in flights and 3 per cent in seat capacity from a year earlier.