Vietnam Sleeper Bus Guide 2025: Toilets, Safety, Booking & Top Companies

vietnam sleeper bus guide 2025 toilets safety booking top companies

Table of Contents

Why Choose a Sleeper Bus? 5 Major Benefits vs Flying & Trains
Cool Benefits:
What to Expect: Sleeper Bus Layout, Seating & Facilities (2025)
Seating Arrangements: Standard vs VIP vs Luxury Sleeper Buses
What's Onboard: Blankets, AC, WiFi, USB Ports & Toilets
 Pros & Cons of Sleeper Buses: Is It Worth Your Money?
Benefits:
Downsides:
Are Sleeper Buses Safe? Safety Tips & How to Choose Bus Companies
Safety Statistics & Reality
Common Safety Concerns (And The Reality)
Top Safe Sleeper Bus Companies (Based on Reviews & Reputation)
On-Bus Safety Practices
What to Do If You Feel Unsafe
Comparing Safety: Sleeper Bus vs Sleeper Train vs Flight
How to Book a Sleeper Bus: 2 Methods (Online & In-Person)
Booking Online: 12Go, Baolau, Vexere & Direct Sites
Booking In-Person: Bus Stations, Agencies & Hostels
Cost Comparison: Online vs App vs In-Person
Booking Tips to Save Money
What to Confirm in Your Booking Confirmation
Do Sleeper Buses Have Toilets? What to Expect at Rest Stops
What to Expect at Rest Stops
How Often Do Buses Stop?
Pro Tips for Toilet Breaks
Choosing Buses with Better Toilet Situations
Why Most Buses Don't Have Toilets
Vietnam Sleeper Bus Prices: Cost by Route Distance (2025)
What to Pack: 6 Essential Items for Sleeper Bus Comfort
Top Sleeper Bus Routes: Hanoi to Sapa, Da Nang, Ho Chi Minh (With Times)
Pro Tips: Best Seats, Motion Sickness & Rest Stop Strategies
Best seat selections:
Figuring Out Rest Stops and Meal Breaks:
Managing Motion Sickness:
Sleeper Bus Alternatives: Trains vs Flights vs Motorbikes
My Hanoi to Ha Giang Sleeper Bus Journey: What Actually Happened
Are Sleeper Buses Worth It? Honest Pros & Cons
First-Time Sleeper Bus Tips: What Experienced Travelers Know
15 Frequently Asked Questions About Vietnam Sleeper Buses

Vietnam sleeper buses, also called overnight buses or night buses, are the cheapest and most flexible way to travel long distances within Vietnam. Are you a backpacker on a tight budget or simply want to save accommodation costs? Well then sleeper buses are for you! Sleeper buses connect Hanoi, Ho Chi Minh City, Da Nang, Sapa, Ha Giang, and dozens of other destinations.

We cover everything you need to know: how to book on 12Go and Vexere, which bus companies are safest (Futa, Sapa Express, The Sinh Tourist), what to expect regarding toilets and rest stops, prices by route (from $8 to $50), seat selection strategies, how to stay safe and comfortable, and insider tips from experienced travelers. Whether you have 5 hours to spare or need to travel 12+ hours overnight, sleeper buses offer direct routes without requiring hotel stays. By the end of this guide, you will know exactly how to book your first sleeper bus and what to expect when you board.


Why Choose a Sleeper Bus? 5 Major Benefits vs Flying & Trains

These buses are literally the most rad and hassle free modes of transportation within Vietnam. Unlike trains that are governed by fixed schedules, these sleeper buses operate multiple times daily and take you directly to great locations such as Sapa, Ha Giang, Hue, Da Nang, and Ho Chi Minh City. They have multiple stops for the destination city so you can choose one closest to your Hotel.

Cool Benefits:

  • Budget-Friendly: Tickets cost between $8 and $40 USD, much less than taking the flight or the train.

  • Save on accommodations: With the night buses, you don't need to reserve accommodation for the evening.

  • Direct Routes: Unlike trains, which require additional transfers, buses go straight to tourist hotspots.

  • Flexible Booking: Book online, through travel agencies, or directly at bus stations.

  • Buses run daily so you've got plenty of possibilities for when it's best to travel by car.

Sleeper buses are not the most glamorous option by far, but they are just about the most convenient thing for backpacker budgets for exploring Vietnam at an affordable cost.


What to Expect: Sleeper Bus Layout, Seating & Facilities (2025)

Seating Arrangements: Standard vs VIP vs Luxury Sleeper Buses

Vietnamese overnight buses are far from the comfortable reclining seats that they offer on European and North American buses. Instead of that, they have bunk-like seats that recline nearly horizontal. Three rows of beds stacked up with tiers above and below are something that you most likely find.

  • Standard sleeper buses contain three compact rows and are generally crowded and uncomfortable.

  • VIP Sleeper Buses: Two wider rows, offering more space and privacy.

  • Luxury sleeper coaches feature these fabulous lie-flat beds, great entertainment systems, and excellent service (more about that momentarily!).

What's Onboard: Blankets, AC, WiFi, USB Ports & Toilets

Most buses include the essentials such as:

  • Blankets & Pillows: Often provided, but can be thin or unwashed—bring your own for comfort!

  • Charging Ports: Buses are sometimes equipped with USB outlets but are generally untrustworthy.

  • WiFi: Advertised but usually unreliable.

  • Air Conditioning: They always blast it, so grab a hood or scarf!


 Pros & Cons of Sleeper Buses: Is It Worth Your Money?

some Higher Priced Buses Offer Pretty Wide Seats Which Are Best for Sleeping on Longer Journeys

Benefits:

  • Affordable: Sleeper buses are the most economical form of travel for lengthy distances within Vietnam.

  • Convenient Routes: Buses go directly to top travel destinations, eliminating the need for transfers.

  • You save the day since overnight travel does not cost the day of travel plus you don’t pay extra for a hotel for sleeping!

  • Flexible Bookings: Book at the last minute or well in advance.

Downsides:

  • Limited Comfort: Even on VIP buses, the seats aren't fully flat, and taller travelers might feel cramped. If you are taller than 6 feet you are in a world of pain!

  • Reckless Driving: Some drivers speed or drive aggressively, making the ride bumpy.

  • Limited Personal Space: The buses are sometimes totally jammed up, so you may find yourself standing beside someone completely asleep.

  • Buses typically need to stop so people can board and alight, making the journey more lengthy.

If you're okay with sacrificing a bit of comfort for the best offer, a sleeper bus is well worth the consideration!


Are Sleeper Buses Safe? Safety Tips & How to Choose Bus Companies

Comfortable interior view of a Vietnam sleeper bus cabin with a turquoise and white patterned bed, cream-colored curtains, and decorative textured ceiling with blue accent lighting

Yes, sleeper buses in Vietnam are generally safe if you book with reputable companies and take basic precautions. However, safety varies significantly depending on the bus company you choose.

Safety Statistics & Reality

According to travel forums and experience from thousands of backpackers: The vast majority of sleeper bus journeys happen without serious incidents. Theft is the most common issue (not accidents). Reckless driving occurs but is less common than perceived. Modern buses with established companies have good safety records.

Common Safety Concerns (And The Reality)

Concern #1: Reckless Driving

Reality: Some drivers do speed or take turns too fast. This is more common on budget buses than VIP services. Choosing reputable companies significantly reduces this risk. If you experience dangerous driving, speak up or get off and rebook.

Concern #2: Theft

Reality: Petty theft from sleeping passengers is the most common issue. This typically involves:

Valuables left in open bunk spaces

Bags with phones or wallets not secured

Money left on beds or in visible pockets

Prevention: Keep passport, phone, and wallet in a small bag under your head or on your body. Lock larger bags if possible. Don't leave valuables visible. Avoid the back rows where thieves target sleeping passengers.

Concern #3: Accidents

Reality: Bus accidents do happen, but are not common on main routes with established companies. Newer buses with better maintenance have fewer mechanical failures. Road conditions on main routes (Hanoi to Ho Chi Minh, Hanoi to Sapa) are reasonably good.

Concern #4: Poor Hygiene / Health Risks

Reality: Sleeper buses can be crowded and are not hospital-clean. Risk of catching minor illnesses is higher than flying. However, serious outbreaks or health crises are rare. Many travelers complete sleeper bus journeys with no health issues.

Futa Bus Lines Comapny Fleet

Top Safe Sleeper Bus Companies (Based on Reviews & Reputation)

5-Star Safety & Comfort (Worth the Premium Price):

The Sinh Tourist: Focuses on tourist comfort, better maintained buses, good reviews

Sapa Express: Specifically for Hanoi to Sapa route, consistently good reviews

Inter Bus Lines: Reliable, modern fleet, popular with backpackers

4-Star (Good Safety, Budget Friendly):

Futa Bus Lines: Large company, decent safety record, more affordable

Queen Cafe VIP Open Bus: Good reputation, varied routes

Mai Linh Express: Established company, reliable

Companies to Avoid:

Unknown companies with no online reviews (Zero information = High risk), companies with consistent complaints about reckless driving, buses offering suspiciously cheap prices (under $8 USD) with poor reviews, operators that lack clear booking information

Safety Checklist Before Booking

Check that the company has at least 100+ Google reviews, Look for recent reviews (within last 2 months), Read reviews specifically mentioning safety and driver behavior, Avoid booking through third parties you cannot verify, Prefer booking directly with the bus company website or through Klook / Viator (verified platforms), Inform someone of your itinerary and bus company name.

On-Bus Safety Practices

When boarding: Inspect the bus for cleanliness and maintenance before committing. If it looks very run-down, ask to change buses. During the journey: Keep valuables on your person, not in your assigned bunk. Avoid the back rows (rougher ride, target area for thieves). Stay in middle bunks (smoother, quieter, safer). Don't leave your bed unattended. Use the restroom during scheduled stops, not during driving time. Keep your phone charged and accessible.

What to Do If You Feel Unsafe

If driver seems reckless: Ask other passengers if they're concerned. Speak to the driver or conductor calmly. Report the issue to the company upon arrival. If you're targeted by another passenger: Alert the driver or conductor immediately. Move to another bunk if possible. Report to your accommodation upon arrival. If you experience theft: Contact the bus company immediately. Report to police if items are valuable. Document the loss for insurance purposes (if applicable).

Comparing Safety: Sleeper Bus vs Sleeper Train vs Flight

Sleeper Bus: Higher accident risk than trains due to driving element, petty theft risk, decent safety record with established companies. Sleeper Train: Safer than buses (no driving, established infrastructure), slightly higher health risk (crowded, shared spaces), very rare accidents. Flight: Statistically safest, most expensive, no time to sleep in transit.

Interior of a Luxury Sleeper Bus in Vietnam Going From Hanoi to Halong Bay


How to Book a Sleeper Bus: 2 Methods (Online & In-Person)

If you want to grab a good seat, it's wise to reserve your bus ticket early particularly if it happens to be travel season like the Tet festival!

Booking Online: 12Go, Baolau, Vexere & Direct Sites

  • Best for advance planning: You can advance book your tickets using websites such as 12Go, Baolau, and the direct bus company websites. I personally love the Vexere app which I consider the best app to book bus tickets in Vietnam since besides buses we can use it for train bookings too and they give an option to book now and pay later to the driver!

  • Filter for VIP Buses: Online platforms often let you choose VIP buses for a more comfortable ride.

  • You'll get the reservation note in English, much more convenient for foreign travellers.

Booking In-Person: Bus Stations, Agencies & Hostels

  • Best for spontaneities: Available at the bus terminals, travel agencies, and most of the hostels.

    Pros: No online service fees, and you may get discounts when negotiating.
    Cons: If the VIP seats are occupied, you could be left stranded on the normal bus.

Cost Comparison: Online vs App vs In-Person

  • Online booking: $8-$40 + 5-10% service fee = $8.40 to $44
  • App booking: $8-$40 (often slightly cheaper than online)
  • In-person cash: $8-$40 with potential 10% negotiation = $7.20-$36

Booking Tips to Save Money

Book during low season (June to September): Prices can drop 20-30%, Book weekday buses instead of weekends: Cheaper, Book earlier in the day (5 AM departures cheaper than 10 PM): Less popular times, Negotiate when booking in-person, Book longer routes for better per-hour value (longer routes = cheaper per hour), Look for promotional codes on 12Go and Vexere (often 10-15% off).

What to Confirm in Your Booking Confirmation

Pickup location and time: Confirm exact street address and time to arrive, Dropoff location and time: Where you'll arrive, expected arrival time, Seat/bunk number: Write it down, Bus company name: Note this for reference, Cancellation policy: Most offer free cancellation 24 hours prior, Your mobile number: Driver will text you before departure, Confirmation reference number: Screenshot this for proof


Do Sleeper Buses Have Toilets? What to Expect at Rest Stops

The honest answer: Most sleeper buses in Vietnam do NOT have onboard toilets, and even those that do are often poorly maintained.

Standard Sleeper Buses: No toilets onboard. Instead, buses stop approximately every 2 to 3 hours at designated rest stops where you can use public facilities.

VIP Sleeper Buses: Some have small onboard toilets, but they are cramped (about 2 meters by 1 meter) and frequently not very clean. Most people I talked to told me that they prefer using rest stop facilities instead.

Luxury Sleeper Buses: Premium services do have better maintained onboard toilets, but these are exceptions rather than the rule.

What to Expect at Rest Stops

Rest stops are typically located at large service stations along the highway. These facilities include:

Squat toilets (traditional Vietnamese style), modern Western style toilets at newer stops, hand washing stations (though not always with soap), canteen areas selling food and snacks, small shops selling souvenirs.

Important: Bring your own toilet paper and hand sanitizer. Many rest stop bathrooms do not provide toilet paper, and cleanliness varies significantly. This is one of the most important things to pack.

How Often Do Buses Stop?

On average: Every 2 to 3 hours for approximately 15 to 20 minutes. On longer journeys (over 12 hours), you may have 3 to 4 toilet breaks. The driver determines stop locations, so you cannot choose where you go. Stops are typically at the same rest areas, so experienced travelers know what to expect on popular routes.

Pro Tips for Toilet Breaks

Use the restroom before boarding to reduce the need for breaks during the journey. At rest stops, go immediately when the bus stops (lines can form quickly). Bring compressed toilet paper packets that take up minimal space. Use hand sanitizer after each restroom visit. Stay hydrated but be strategic about drinking too much liquid that will require frequent bathroom breaks.

Choosing Buses with Better Toilet Situations

If onboard toilet access is important to you, book luxury sleeper buses (higher cost but better amenities). Choose overnight buses that reach your destination by early morning, reducing total travel time. Book direct routes that minimize stops rather than buses with multiple pickups along the route. Read reviews on Google and Booking platforms specifically mentioning toilet conditions.

Why Most Buses Don't Have Toilets

The reason most buses lack onboard toilets is practical: Adding toilets reduces sleeping space, increases maintenance complexity, and doesn't significantly increase ticket prices. Buses are designed to maximize bunk beds and minimize amenities costs. Rest stops work fine for the typical 5 to 12 hour journeys that Vietnamese sleeper buses operate.


 Toilet and Hanwash in a Sleeper Bus Travelling From Ho Chi Minh City


Vietnam Sleeper Bus Prices: Cost by Route Distance (2025)

Here's the quick rundown of the cost for you:

  • Short Routes 5-7 hours: $8-$15 USD .

  • Medium Routes (8-12 hours): $15-$25 USD

  • Long trips (> 12 hours): $40-$65 USD

  • Luxury Sleeper Buses: $30-$50 USD for extra comfort

Keep an ear for supplementary fees:

  • Last-minute bookings may cost more.

  • Some companies charge more cash for the larger bags.

  • VIP and luxury buses may be a bit pricey, but they're absolutely worth it for long journeys.

Modern Vietnam sleeper bus interior with blue neon ambient lighting, corrugated metal walls, individual bunk beds with side reading lights, and premium cabin design


What to Pack: 6 Essential Items for Sleeper Bus Comfort

A little preparation goes a long way. Here's what to bring for a smooth trip:

  • Earplugs & Eye Mask: Blocks out honking, music, and overhead lights.

  • Water Bottle: Stay hydrated, as some buses don't provide water.

  • Snacks: Meal stops can be unpredictable, so pack something reliable.

  • Power Bank: Charging ports may not work, so bring a backup.

  • Warm Clothing: Buses blow out the A/C, don't they? It gets really cold there!

  • Slip-on shoes: easy peasy to slip off while horizontal.


Top Sleeper Bus Routes: Hanoi to Sapa, Da Nang, Ho Chi Minh (With Times)

  • Hanoi to Sapa: 5-6 hours, faster and more flexible than the train.

  • Hanoi to Ha Giang is 6-7 hours, and that's the best for exploring the Ha Giang Loop.

  • Hanoi to Hue: 12-14 hours, overnight travel saves sightseeing time.

  • Da Nang to Nha Trang: 9-10 hours, with modern bus options available.

  • Ho Chi Minh City to Mui Ne: 5-6 hours, a quick and scenic route.

Mini Tip: Some buses arrive at odd hours, like 3 AM—check arrival times before booking. If you are staying in a homestay, some of them offer personal pickup from the bus stop free of cost. But do check in advance when booking your stay.

Da Nang to Nha Trang Route Is Quite Scenic


Pro Tips: Best Seats, Motion Sickness & Rest Stop Strategies

Best seat selections:

  • Middle bunks are ideal which avoids the bumpy back and noisy front.

  • The upper bunks are somewhat private but are rather inconvenient to get up to.

Figuring Out Rest Stops and Meal Breaks:

  • Rest stops happen every 2-3 hours so bring small change for food or snacks.

  • Always carry tissues as rest stop bathrooms may lack toilet paper.

Managing Motion Sickness:

  • Sit in the middle for the smoothest ride.

  • Bring motion sickness tablets if you're prone to nausea.


Sleeper Bus Alternatives: Trains vs Flights vs Motorbikes

  • Overnight Trains: More comfortable, quieter, and smoother than buses, but pricier.

  • Budget Flights: Faster but can cost slightly more, especially with baggage fees.

  • Day buses are good for short distances but are likely not that comfortable.

  • Motorbike trips are ideal for adventure-seekers, particularly on great roads such as the Hai Van Pass.
    Hai Van Pass Has Good Quality Roads for Motorbike Tours


My Hanoi to Ha Giang Sleeper Bus Journey: What Actually Happened

I've done heaps of Vietnamese sleeper buses throughout Vietnam. Of all of these, the journey from Hanoi to Ha Giang just lingered with me.

I booked a VIP sleeper bus, expecting comfort, but ended up squeezed between a snoring traveler and a backpacker who decided to take off their shoes (bad idea). The driver honked every few minutes, making it tough to sleep. But despite the discomfort, I loved watching the Vietnamese countryside roll past during the early evening. When I finally arrived, I was exhausted but ready to start my Ha Giang Loop tour after catching a couple hours of nap in a homestay in Ha Giang!


Are Sleeper Buses Worth It? Honest Pros & Cons

Yes, if you're on a budget! They're cheap, direct, and save on accommodation.

No, if you prioritize comfort. Overnight trains or flights are better if you need proper sleep. Also if you are taller than 6 feet, you might not be able to stretch your legs completely as most sleeper buses I traveled in max out at around 180 cm which is close to 6 feet. You can still sleep but will have to sleep sideways or bend your legs a bit.

First-Time Sleeper Bus Tips: What Experienced Travelers Know

  • Book VIP or Luxury if possible as it makes a big difference.

  • Prepare for delays as Vietnamese roads can be unpredictable.


15 Frequently Asked Questions About Vietnam Sleeper Buses

Q1. Are sleeper buses safe in Vietnam?
Yes, sleeper buses in Vietnam are generally safe if you book with reputable companies after checking their reviews online and take basic precautions. However, safety varies significantly depending on the bus company you choose.

Q2. Do Sleeper Buses in Vietnam Have Toilets?
Majority of sleeper buses in Vietnam do NOT have onboard toilets and even those that do are often poorly maintained.

Q3: What is the Best Sleeper Bus Company in Vietnam?
For Hanoi to Sapa: Sapa Express or Inter Bus Lines (highly reviewed). For multiple routes: Futa Bus Lines or The Sinh Tourist. For luxury: Mai Linh Express or inter Bus Lines. Check Google reviews and ensure at least 100+ ratings before booking. Companies with 4.5+ stars consistently have fewer complaints about safety and comfort.

Q4: How Much Do Sleeper Bus Tickets Cost?
Short routes (5-7 hours): $8 to $15 USD. Medium routes (8-12 hours): $15 to $25 USD. Long routes (over 12 hours): $25 to $40 USD. VIP buses add $5 to $10. Luxury sleeper cabins cost $30 to $50. Budget travel (standard buses) starts at $8, premium experiences can reach $50. Book online or via app for consistent pricing; in-person booking may offer discounts.

Q5: What is a VIP Sleeper Bus vs Standard?
Standard: 40+ narrow bunks, basic amenities, cheapest. VIP: 20-30 wider bunks, more legroom, better blankets/pillows, slightly quieter, $5-10 more expensive. Luxury: Premium beds, private curtains, entertainment system, quality food service, $20-30 more expensive. Choose based on budget and comfort needs. VIP is best for most travelers seeking balance of comfort and cost.

Q6: How Long is the Bus Ride from Hanoi to Sapa?
Sleeper bus: 5.5 to 6 hours direct. Sleeper train (alternative): 8 to 9 hours on train plus 1 hour transfer = 9 to 10 hours total. Bus is faster and goes direct to Sapa town (no transfer needed). Train is smoother but requires getting to/from Lao Cai train station.

Q7: What Should I Bring on a Sleeper Bus?
Essential: Passport, phone, wallet (keep on your person). Comfort: Earplugs, eye mask, extra clothing, power bank. Hygiene: Toilet paper, hand sanitizer, tissues, wet wipes. Toiletries: Toothbrush, toothpaste, deodorant. Optional: Pillow, lightweight blanket, camera. DO NOT bring: Large suitcases (they go under bus), valuables like jewelry, excess luggage (bunks are small).

Q8: Should I Eat Before or During the Bus Ride?
Eat a light meal before boarding (1-2 hours). Rest stops have food but quality/freshness varies. Bring snacks (nuts, chocolate, crackers). Bring empty water bottle to fill at rest stops. Avoid heavy meals that cause motion sickness. Stay hydrated but be strategic about liquid intake (limit bathroom breaks). Do NOT rely on rest stop food if you have dietary restrictions.

Q9: Do Sleeper Buses Provide Blankets and Pillows?
Blankets: Almost always provided (usually thin or used, quality varies). Pillows: Rarely provided; bring your own or use a small bag/jacket. Sheets: Sometimes provided but not always clean; consider bringing a lightweight sleep sack. Many travelers bring their own lightweight blanket for comfort and hygiene. Luxury buses typically provide better quality bedding.

Q10: Is Motion Sickness Common on Sleeper Buses?
Yes, for some travelers. Causes: Narrow bunks, curved roads, continuous driving. Prevention: Choose middle bunks (smoothest), sit upright during day sections, bring motion sickness tablets (Dramamine, Bonine), avoid looking at phone during driving, eat light meals. If motion sick: Move to different bunk, take medication early, use acupressure bands, distract yourself with music/podcasts.

Q11: Can I Book a Private Double Cabin on a Sleeper Bus?
Yes, available on many routes. Cost: $30 to $60 for 2 people. Capacity: Usually 2 people per cabin (some have 3). Booking: Request specifically when booking online or in-person. These are more private and comfortable but more expensive. Popular on Hanoi to Sapa, Da Nang to Ho Chi Minh. Reserve early in high season as double cabins book quickly.

Q12: What's the Difference Between Sleeper Bus vs Sleeper Train in Vietnam?
Bus faster (5-6 hours vs 9-10 hours with train transfer), costs less ($15-30 vs $30-60), reaches more destinations, rougher ride. Train smoother, quieter, more space, safer, costs more, limited routes (only main north-south line), requires transfer to/from station. Choose bus for speed/price, choose train for comfort/safety.

Q13: How Early Should I Arrive Before the Bus Departs?
Arrive 15 to 20 minutes before departure. Buses do NOT wait for late passengers. Drivers may leave 5-10 minutes early if fully loaded. Pickup locations can change, so confirm in your confirmation email. Plan to arrive 30 minutes early if unsure of location. Be extra early during peak season or holidays.

Q14: Can I Cancel or Change My Sleeper Bus Booking?
Most platforms allow free cancellation 24 hours before departure. Cancellation after 24 hours usually loses full payment. Some platforms charge $5-10 cancellation fee. Check specific platform terms when booking. Last-minute cancellations rarely refund. Changes to date/time: Usually free if done 24+ hours prior. Contact company/booking platform directly for changes.

Q15: Will I Actually be able to sleep on an overnight Vietnamese sleeper bus?
Honest answer: Maybe. For some people: Yes, especially if tired or on longer routes. For others: Difficult due to noise, discomfort, or unfamiliar environment. Factors affecting sleep: Your sleep ability, bus quality, route type (smooth highways vs mountain roads), noise level, bunk location and how tall are you. 
Tips to sleep: Earplugs + eye mask are essential, choose middle bunks, take melatonin or sleep aid if comfortable, avoid caffeine, wear comfortable clothing, adjust expectations (partial sleep is common, not 8 hours of deep sleep).