Planning a journey across Southeast Asia can be both exciting and overwhelming, especially when you want to make the most of your time. If you’re considering spending 21 days in Vietnam and Thailand, you’re in for an unforgettable adventure filled with vibrant cultures, stunning landscapes, and rich histories. This complete 2025 guide will help you navigate through the best experiences both countries have to offer, ensuring that you get the perfect blend of iconic sites, hidden gems, and local flavors. Whether you’re exploring the bustling streets of Hanoi, cruising through Halong Bay, or soaking up the energy of Bangkok, this guide will provide you with a well-rounded itinerary to make your 21-day journey truly memorable.
Steps to Plan a Trip to Vietnam and Thailand
Choose the Best Time to Visit Vietnam and Thailand
The best time to visit Vietnam and Thailand largely depends on the weather patterns and what kind of experiences you’re looking for. Both countries have tropical climates with distinct seasons, making certain times of the year more favorable for travel.
Vietnam Weather
In Vietnam, the ideal time to visit is from November to April. During these months, the weather is generally cooler and drier across the country. In the north, cities like Hanoi and Halong Bay experience mild temperatures and less rainfall, making it perfect for exploring cultural sites and taking scenic cruises. Central Vietnam, including destinations like Hoi An and Hue, also enjoys pleasant weather, though it can be cooler in January and February. The southern regions, including Ho Chi Minh City and the Mekong Delta, are warm and dry, making it an excellent time for outdoor activities and river cruises.
Thailand Weather
For Thailand, the best time to visit is during the cool and dry season from November to February. This period offers comfortable temperatures, particularly in Bangkok, Chiang Mai, and the islands like Phuket and Koh Samui. The weather is ideal for beach activities, island hopping, and exploring the rich cultural heritage of the country. The cool season also coincides with several major festivals, including Loi Krathong in November, adding a cultural dimension to your trip.
>>> For more information, you can check out our articles on Thailand’s weather guide and weather in Vietnam.
Apply for Vietnam and Thailand Visas
Depending on your nationality, you may or may not need to apply for Vietnam and Thailand visas.
From August 15, 2023, many nationalities can enter Vietnam visa-free for up to 45 days, including Japan, South Korea, the United Kingdom, France, Sweden, Germany, etc. If you are not on this list, you can apply for a Vietnam E-visa and can stay in the country for up to 90 days. Click here to check the detailed requirements for a Vietnam visa.
For Thailand, many nationalities can also enter visa-free under the visa exemption rule, which typically allows for a stay of up to 60 days and can be extended for 30 more days. This applies to visitors from 93 countries, including the United States, Canada, the UK, Australia, and most European countries. Travelers from other countries and territories can apply for a Visa on Arrival.
Generally speaking, you won’t need to apply for visas for your 21-day tour to both countries. However, it’s crucial to check the latest visa requirements from the official embassy websites or trusted travel resources, as visa policies can change. Always ensure your passport is valid for at least 6 months beyond your planned date of entry into each country.
Plan Your Budget for 21 Days in Vietnam and Thailand
Depending on your personal preference and travel guide, the expense can vary. If you are a budget traveler, you might need around $1,500 to $2,000, covering basic accommodations, local food, transportation, and activities. For a more comfortable experience with mid-range hotels, guided tours, and occasional splurges, a budget of $3,000 to $4,000 would be appropriate. If you prefer luxury travel, staying in high-end hotels, dining at fine restaurants, and enjoying premium experiences, you should plan for a budget of $5,000 or more. This estimate includes all major expenses, but personal spending and shopping will add to the overall cost.
Check Essential Packing Lists
Luggage Packing Consideration
When packing for 21 days in Vietnam and Thailand, it’s important to prepare for a range of climates and activities. Start with lightweight, breathable clothing suitable for the tropical climate, including shorts, t-shirts, and light dresses. A few long-sleeved shirts and pants are essential for protection against mosquitoes, especially in the evenings, and for visiting temples where modest attire is required.
Comfortable walking shoes are a must for exploring cities, as well as sandals for beach days. Don’t forget a rain jacket or poncho, as sudden showers are common, particularly during the rainy season. A wide-brimmed hat, sunglasses, and sunscreen are crucial for sun protection.
For personal care, pack travel-sized toiletries, including insect repellent, hand sanitizer, and any prescription medications. A reusable water bottle with a good filtration system is also handy, especially in areas where tap water isn’t safe to drink.
Electronics-wise, bring a universal power adapter, a portable charger, and waterproof cases for your devices. A lightweight backpack for day trips and a secure money belt or pouch for your valuables will help keep your belongings safe.
Lastly, don’t forget essential travel documents, including your passport (with at least six months of validity), copies of your travel insurance, visa information, and itinerary details. A small first aid kit with basic supplies like band-aids, pain relievers, and motion sickness tablets is also recommended.
Suggested Itineraries for 3 Weeks in Vietnam and Thailand
Itinerary 1: Discover Vietnam and Thailand from the City to the Mountain
Day 1: Arrive in Hanoi
Day 2: Hanoi city tour
Day 3: Visit Bat Trang Pottery Village & Hanoi night street food tour
Day 4: Transfer to Ha Long Bay & embark on an overnight cruise to discover this UNESCO World Heritage Site of Vietnam
Day 5: Return to Hanoi & Overnight train to Lao Cai
Day 6: Drive to Sapa & visit hill tribe villages
Day 7: Climb Mount Fansipan & Overnight train to Hanoi
Day 8: Fly to Da Nang, Visit Ba Na Hills & the Golden Bridge
Day 9: Day tour to Hoi An Ancient Town
Day 10: Fly to Bangkok
Day 11: Bangkok city tour
Day 12: Day tour to Ayutthaya Historical Park
Day 13: Fly to Chiang Mai & Join an evening food tour
Day 14: Day trip to Doi Inthanon National Park
Day 15: Day tour to Lamphun
Day 16: Fly to Surat Thani & Travel to Khao Sok National Park
Day 17: River rafting at Khao Sok National Park
Day 18: Transfer to Khao Lak
Day 19: Discover Similan Islands
Day 20: Kayak in the mangrove forest of Khao Lak
Day 21: Transfer to Phuket & Departure.
>>> Click this link for the detailed itinerary of this tour.
Itinerary 2: Authentic Vietnam and Thailand in 3 Weeks
Day 1: Arrive in Ho Chi Minh City
Day 2: Ho Chi Minh City – Mekong Delta
Day 3: Visit a floating market, return to Ho Chi Minh City, fly to Da Nang & travel to Hoi An Ancient Town
Day 4: Hoi An city tour
Day 5: Visit Tra Que Herbal Village & join a cooking class
Day 6: Transfer to Da Nang, fly to Hanoi & embark on a half-day city tour
Day 7: Drive to Sapa & Visit Ta Giang Phinh Village
Day 8: Trekking in Sapa
Day 9: Discover the Heaven’s Gate & Return to Hanoi
Day 10: Hanoi – Ha Long Bay, embark on an overnight cruise
Day 11: Return to Hanoi & Fly to Bangkok
Day 12: Bangkok city tour
Day 13: Visit Damnoen Saduak & Mae Klong markets
Day 14: Fly to Chiang Mai & Join a cooking class
Day 15: Chiang Mai temple tour
Day 16: Visit an elephant sanctuary in Chiang Mai
Day 17: Discover Chiang Mai’s countryside & visit hill tribe villages
Day 18: Fly to Phuket
Day 19: Day tour to Phi Phi & Khai Islands
Day 20: Free day in Phuket
Day 21: Depart Phuket.
>>> Detailed itinerary: Vietnam – Thailand 21 days authentic experience.
Itinerary 3: Extend to Cambodia for a Rounded Experience
Day 1: Arrive in Hanoi
Day 2: Hanoi city tour
Day 3: Hanoi – Ha Long Bay & embark on an overnight cruise
Day 4: Return to Hanoi & fly to Da Nang
Day 5: Visit Ba Na Hills & the Golden Bridge
Day 6: Day tour to Hoi An Ancient Town & Bay Mau Coconut Forest
Day 7: Free day in Da Nang
Day 8: Fly to Siem Reap & Join a half-day Angkor tour
Day 9: Angkor temple tour
Day 10: Discover Phnom Kulen Mountains & Banteay Srei
Day 11: Explore Tonle Sap Lake & Fly to Bangkok
Day 12: Bangkok city tour
Day 13: Day tour to Ayutthaya
Day 14: Fly to Phuket & Join a half-day city tour
Day 15: Discover Koh Phi Phi by speedboat
Day 16: Discover James Bond Island
Day 17: Free day in Phuket
Day 18: Fly to Chiang Mai
Day 19: Chiang Mai city tour
Day 20: Visit a hill tribe village and the Golden Triangle
Day 21: Depart Chiang Mai.
>>> If you are interested in this itinerary, please refer to our Explore the Majestic Beauty of Vietnam – Cambodia – Thailand in 21 Days.
Budget Estimation for 21 Days in Vietnam and Thailand
A Breakdown of Cost
Here’s a breakdown of the cost for a 21-day trip to Vietnam and Thailand, covering essentials like accommodation, food, transportation, activities, and miscellaneous expenses. The costs are approximate and will vary depending on your travel style – budget, mid-range, or luxury.
1. Accommodation
- Budget: $15-30 per night (Hostels, budget hotels)
- Mid-Range: $40-100 per night (3-4 star hotels)
- Luxury: $150-300+ per night (5-star hotels, resorts)
2. Food
- Budget: $10-20 per day (Street food, local eateries)
- Mid-Range: $25-50 per day (Casual dining, local restaurants)
- Luxury: $75-150+ per day (Fine dining, upscale restaurants)
3. Transportation
- Flights between Vietnam and Thailand: $50-150 per flight (3-4 flights)
- Local Transportation: $5-15 per day (buses, taxis, tuk-tuks)
4. Activities and Excursions
- Budget: $10-25 per day (self-guided tours, entry fees)
- Mid-Range: $30-70 per day (guided tours, boat trips)
- Luxury: $100-200+ per day (private tours, premium experiences)
5. Miscellaneous
- Visa Fees: $50-100 per country (depending on nationality)
- Travel Insurance: $50-150 (for 21 days)
- Souvenirs/Shopping: $100-500
Total Estimated Costs
- Budget: $1,090 – 2,140
- Mid-Range: $2,305 – 5,185
- Luxury: $6,975 – 14,800
Budget estimate for 21 days in Vietnam and Thailand
This breakdown offers a general idea of the costs associated with 3 weeks in Vietnam and Thailand. Your total cost will depend on your travel preferences and any additional activities or services you choose to include.
Tips to Save Money for your Vietnam – Thailand Trips
- Book Flights Early: Purchase your international and domestic flights well in advance to secure the best deals.
- Travel During Shoulder Seasons: Visiting just before or after peak seasons can reduce costs on flights and accommodations while still offering pleasant weather.
- Use Public Transportation: Opt for buses, trains, and tuk-tuks over taxis and private cars to save on local transportation.
- Stay in Budget Accommodations: Consider staying in hostels, guesthouses, or budget hotels instead of luxury resorts.
- Eat Local: Enjoy street food and dine at local eateries where meals are much cheaper and offer authentic experiences.
- Bargain at Markets: Negotiate prices in markets and with street vendors to get better deals on souvenirs and goods.
- Free and Low-Cost Activities: Take advantage of free or low-cost attractions like temples, beaches, and walking tours.
- Limit Alcohol Consumption: Alcohol can be expensive, so limiting your consumption or buying from local shops rather than bars can save you money.
- Use Travel Apps and Discounts: Look for deals on travel apps or websites, and use discount cards or passes when available.
- Carry a Reusable Water Bottle: Refill your water bottle instead of constantly buying bottled water, saving money and reducing plastic waste.
Spending 21 days in Vietnam and Thailand offers an incredible opportunity to immerse yourself in the rich cultures, stunning landscapes, and diverse experiences these two countries have to offer. From exploring the bustling streets of Hanoi and Bangkok to relaxing on the beaches of Phuket and Halong Bay, the above-suggested itineraries ensure you get the best of both worlds.
Don’t hesitate to contact us if you are eager to discover the wonders of Vietnam and Thailand but still don’t know where to start. We are ready to help you craft a perfect itinerary for your personal preferences.
