Customer Service Numbers: Should You Choose 1900, 1800, or a Landline? Cost Comparison 2026

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Choosing a customer service number might seem like a small matter, but it’s a decision businesses will live with for years: once the number is printed on packaging, signage, and contracts, it’s very difficult to change. Choosing the wrong one not only wastes money but also creates a barrier that makes customers hesitant to call. This article compares three popular options—1900, 1800, and landline—based on crucial decision-making criteria, including actual costs and how to operate a hotline to ensure no calls are missed.

What is a customer service number?  It’s a phone number published by a business for customers to contact for advice, technical support, warranty, or complaints. Three common options in Vietnam are  1900 numbers  (callers pay the call, the business receives a revenue share),  1800 numbers  (toll-free for callers, the business pays entirely), and  fixed-line numbers based on area codes  (028, 024, etc.). The common point: all three require a call center system; otherwise, they will constantly show a busy signal.

Quick summary

• Want more calls from customers?  Choose 1800 — free for callers, removing psychological barriers.
• To make calls self-sustaining:  Choose 1900 — customers pay the call charges, businesses receive a 35–37% commission on revenue.
• Need a representative office number, small budget:  Choose a landline number — lowest cost, familiar, but includes an area code.
• Estimated costs:  1900 subscribers 1,100,000 VND/month; 1800 subscribers 550,000 VND/month plus a 5,000,000 VND deposit and call minutes charges.
• The real deciding factor:  It’s not about which number to choose, but whether there’s a call distribution center behind that number.
• Key metrics to monitor:  Missed call rate and average wait time — these two figures reveal most of the hotline’s problems.

1. Why is choosing the right customer service number important?

Customer service is the point of contact customers turn to when they  need help the most  —defective products, delayed orders, not knowing how to use a product. The experience at that moment determines whether they stay or leave.

Three factors in number selection directly impact this experience:

• The cost barrier.  If calling costs money, a segment of customers will not call — they will post on social media or quietly switch to a competitor.
• Memorability is key.  Short, easy-to-remember numbers are called far more often than long numbers with area codes, especially when printed on packaging or billboards.
• Long-term stability.  1900 and 1800 numbers do not have area codes, so they remain the same when moving offices. Fixed-line numbers are linked to the province or city where they are registered.

2. Three types of numbers and the characteristics of each type.

1900 numbers — customer-paid.  This is the most widely used type of call center in Vietnam. Callers pay between 1,000 and 15,000 VND per minute, depending on the number, and the business receives  35-40% of the call revenue from the network provider . This mechanism both generates revenue to offset operating costs and filters out non-serious calls. In return, it creates a barrier for customers who genuinely need support.

Three common types of customer service numbers

1800 numbers are paid for by the business.  Calls are completely free, including intercity calls. The business bears all costs. This type of number is used by large brands for warranty and technical support hotlines, where the goal is  to encourage customers to call  , not to discourage them.

Fixed-line numbers are assigned by area code.  Traditional prefixes are linked to specific localities — 028 for Ho Chi Minh City, 024 for Hanoi. The advantages are the lowest cost, simple procedures, and the feeling that the business has a physical office. With current virtual PBX technology, fixed-line numbers can still be used anywhere with internet access and remain unchanged when relocating offices.

3. Detailed comparison table

Three customer service number options

Criteria	1900 number	1800 number	Fixed number
Who pays the fare?	Client	Businesses	Client
Monthly subscription fee	1.100.000 VNĐ	Từ 550.000 VNĐ	Lowest
Deposit	Optional	5,000,000 VND (refundable upon liquidation)	Are not
Reverse revenue	35–40% discount	Are not	Are not
Attach area code	Are not	Are not	Have
Barriers to customers	High — please consider this before calling.	Do not have	Low — standard rate
Most suitable	The consultation hotline is subject to a fee.	Warranty and complaint hotline	Office Representative Number

4. Which customer service number should you choose for your business?

Four common scenarios and corresponding options:

New businesses with limited budgets and fewer than 10 employees  can start with  a fixed line number and a virtual PBX . This is the lowest cost option and includes features like extension and call recording. As the brand grows, upgrade to a service number.

Businesses with products requiring warranty and after-sales support  should choose  1800. The cost per minute is well worth it if it helps get your complaint heard directly instead of on social media.

Businesses with specialized consulting services and a high volume of calls  should choose  the 1900 hotline. Revenue discounts help the hotline cover its operating costs while filtering out non-serious calls.

When should you use a combination of multiple numbers?

Brands run nationwide campaigns.  Priority is  given to short, easy-to-remember service numbers  (1900 or 1800 depending on target audience). These numbers can be printed on packaging, signage, TV commercials, and are not area-dependent.

Many businesses opt for a combined approach: a fixed number as a representative number on legal documents, and a 1800 number as a support hotline. Both lead to a single call center.

5. Customer care number registration process

Steps to register for a customer service number.

The entire process usually takes  5–10 business days . Basic documents include the business registration certificate and the legal representative’s identification. The national telecommunications number pool is allocated by the state management agency — planning information is published on  the Telecommunications Authority’s portal .

A note on number selection: if your business plans to print this number on packaging or run long-term advertising campaigns, take the time to choose a memorable sequence. The cost difference for a nice number is often much smaller than the marketing value it provides over many years.

6. Operate the hotline to ensure no calls are missed.

Having a nice-looking customer service number that nobody answers is worse than having no hotline at all. Four things to do immediately after connecting:

• Configure the Informative Response (IVR) greeting and keypad menu.  Direct customers to the correct department from the start, reducing waiting time and eliminating most repetitive questions.
• Group call distribution.  Calls are automatically transferred to another line when the first line is busy, instead of being told the caller is busy.
• Turn on full audio recording.  This is essential for staff training and dispute resolution. It’s also the best source of data to understand what customers are actually asking.
• Track missed calls and call them back.  Each missed call represents a customer in need of assistance who is not receiving help. The system should send an alert so the team can call them back later that day.

Outside of business hours,  AI callbots can be added  to receive information and schedule follow-up calls — so customers don’t have to listen to a phone ringing in the air.

7. 4 common mistakes

Mistake 1: Choosing a number based on price instead of goals.  If the goal is to increase the number of responding customers, choosing 1900 because it’s cheaper for the business goes against that goal.

Mistake 2: Using a personal mobile number as a hotline.  When an employee leaves, they take with them the entire customer contact history. No recording, no reporting, and no forwarding.

Mistake 3: Registering a phone number without a dedicated switchboard.  Some services routed to a single extension will constantly be busy during peak hours.

Mistake 4: Lack of measurement.  Without knowing the missed call rate or which hours are overloaded, improvement is impossible. This is why choosing a call center with real-time reporting is crucial.

8. Frequently Asked Questions

Should you choose a customer service number, 1900 or 1800?
Choose 1800 if you want to encourage customers to call – suitable for warranty hotlines, technical support, and complaints. Choose 1900 if you want to self-fund calls and filter out non-serious calls – suitable for specialized customer service call centers.

Is calling 1800 free?
No. Callers are completely exempt from charges, including long-distance calls. The company that owns the number pays all the costs.

What are the maintenance costs for a customer service number?
A 1900 number costs approximately 1,100,000 VND/month. An 1800 number costs from 550,000 VND/month plus a 5,000,000 VND deposit and call minute charges. Fixed-line numbers have the lowest cost among the three types.

Do I need to change my phone number when moving offices?
No, for 1900 and 1800 numbers, as they don’t have area codes. For fixed-line numbers used through a virtual switchboard, the number remains the same when moving offices.

Where should small businesses start?
A fixed line number combined with a virtual PBX is a reasonable starting point: low cost, still provides IVR, call distribution, and recording. As call volume increases, upgrade to a service number.

Can a business use multiple numbers simultaneously?
Yes. A common model is to have one fixed line number as a representative number and a 1800 number as a support hotline, both connecting to a single call center for centralized management.

9. Conclusion

Choosing a customer service number is essentially choosing who will pay for the calls — and thus, determining how easily customers can reach you. If the priority is removing barriers, 1800 is the obvious choice. If the hotline needs to be self-sustaining, 1900 is more reasonable. If the budget is limited, a fixed line number with a virtual call center is a good starting point. But no matter which number you choose,  the deciding factor in the experience lies in the system behind it : does it distribute calls effectively, does it record calls, and do you know how many calls you’re missing each day?

OMICall offers 1900, 1800, and fixed-line numbers along with a multi-channel virtual call center platform: IVR greetings, departmental call distribution, automatic call recording, customer information display when the phone rings, and real-time missed call reporting. Businesses can retain their existing numbers when relocating offices. Contact us for advice on choosing the right number for your business model.

For further information, please contact:

VIHAT TECHNOLOGY Co., Ltd

Headquarters: ViHAT Building – 06 Street No. 16 (Him Lam Residential Area) – Hiep Binh Chanh Ward – Thu Duc District – Ho Chi Minh City

Hanoi Branch: Floor 15, LADECO Building, 266 Doi Can, Ba Dinh, Hanoi

Cambodia Branch: Thida Rath #154 St. 33MC, Sangkat Steung Meanchey, Khan Mean Chey, Phnom Penh