Is $20 per day realistic for the whole country?

Yes, but Ho Chi Minh City and Hanoi are more expensive than smaller cities. You might spend $22-25 in major cities and $15-18 in places like Hoi An or Hue, so it averages out.

What if I want some comfort occasionally?

Budget an extra $10-15 every few days for a private room with AC, or $20 for a nice meal. Just balance it with cheaper days eating only street food.

How much should I budget for Ha Long Bay?

Day trips start at $25. If you want to do it on this budget, skip other activities that week and eat super cheap for a few days to offset the cost.

Is it safe to eat street food on this budget?

Absolutely. Look for high turnover - places packed with locals. Avoid anything that's been sitting out. Your stomach might need 2-3 days to adjust regardless of where you eat.

How to travel Vietnam on $20 per day

Vietnam on $20 per day is absolutely doable if you stay in dorms, eat local street food, and use overnight buses between cities. Sleep in hostels ($3-6), eat pho and banh mi ($1-3 per meal), and budget $8-12 for transport on travel days.

Book dorm beds, not private rooms. Hostels charge $3-6 per night for dorms in major cities. Book 2-3 days ahead through Hostelworld or walk-ins work in most places except peak season (December-February). Private rooms start at $12+ and will blow your budget.
Eat where locals eat. Street food and local restaurants charge $1-3 per meal. Look for plastic stools on sidewalks - that's where you'll find the best pho for $1.50. Western food costs $8-15 per meal and will destroy your budget fast.
Use overnight buses for long distances. Overnight buses cost $8-15 and save you a hotel night. Book through your hostel or at bus stations. Day buses cost the same but you'll need accommodation. Domestic flights start at $40+ and don't fit this budget.
Skip expensive tourist traps. Free walking tours, temples ($1-2 entry), and markets cost almost nothing. Ha Long Bay day trips start at $25 but overnight tours cost $60+. Stick to free activities and budget attractions under $5.
Negotiate everything. Taxis, motorbike taxis, souvenirs - everything is negotiable. Start at half the asking price. Use Grab for transparent pricing when you don't want to negotiate. Local buses cost under $1 vs $5+ for tourist buses.

Is $20 per day realistic for the whole country?: Yes, but Ho Chi Minh City and Hanoi are more expensive than smaller cities. You might spend $22-25 in major cities and $15-18 in places like Hoi An or Hue, so it averages out.
What if I want some comfort occasionally?: Budget an extra $10-15 every few days for a private room with AC, or $20 for a nice meal. Just balance it with cheaper days eating only street food.
How much should I budget for Ha Long Bay?: Day trips start at $25. If you want to do it on this budget, skip other activities that week and eat super cheap for a few days to offset the cost.
Is it safe to eat street food on this budget?: Absolutely. Look for high turnover - places packed with locals. Avoid anything that's been sitting out. Your stomach might need 2-3 days to adjust regardless of where you eat.