The range at a glance
8-Port 2G GSM Modem Pool
8 SIM channels · 2G GSM (Wavecom Q2403-class) · USB 2.0 · SMA antenna ports
£305
Available to order, dispatched in 3 to 5 weeks
64-port 2G/3G model is £144 more with 8× the channels, from UK stock.
Details and order
16-Port 2G GSM Modem Pool
16 SIM channels · 2G GSM (Wavecom Q2403-class) · USB 2.0 · SMA antenna ports
£545
Available to order, dispatched in 3 to 5 weeks
64-port 2G/3G model is £96 less with 4× the channels, from UK stock.
Details and order
32-Port 2G GSM Modem Pool
32 SIM channels · 2G GSM (Wavecom Q2403-class) · USB 2.0 · SMA antenna ports
£1,040
Available to order, dispatched in 3 to 5 weeks
64-port 2G/3G model is £591 less with 2× the channels, from UK stock.
Details and order
64-Port 2G/3G GSM Modem Pool
64 SIM channels · USB 2.0 · SMA antenna ports · UK stock
£449 £539
In stock, 22 units available
View and buyAll four share the same construction: removable modem modules (2G/3G on the 64-port, 2G on the smaller units), one SIM holder and one SMA antenna socket per channel, a USB host connection and standard AT-command control on Windows or Linux. They differ in channel count, chassis size, price and availability: the 64-port is held in UK stock, while the 8, 16 and 32-port 2G units are made to order with a 3 to 5 week lead time. Because the 64-port costs far less per channel, most buyers who arrive looking for a 16 or 32-port pool choose the 64-port and populate it gradually.
What a GSM modem pool is for
A single USB GSM modem gives you one SIM and one conversation at a time. A modem pool multiplies that: 64 modems means 64 SIMs, 64 phone numbers and 64 simultaneous SMS sessions, all managed from one computer. That is the difference between sending a few hundred messages a day and running a proper messaging service.
The reasons organisations choose their own pool rather than a cloud SMS API usually come down to control and cost at volume. With a pool you own the SIMs and the numbers, messages leave from your premises, inbound replies land in your own software, and there is no per-message platform fee on top of the SIM tariff. Typical users include appointment-heavy businesses (clinics, garages, salons, letting agents), logistics and delivery operators, alarm and telemetry companies collecting machine-to-machine messages, and telecoms firms running test beds. For a fuller explanation of the hardware see what is a GSM modem pool?
How to choose the right size
Three questions decide it:
- Peak sending rate. A GSM channel completes roughly one standard SMS every 6 to 10 seconds, so plan on around 360 to 600 messages per channel per hour in good signal. Divide your busiest hour by that figure to get a minimum channel count, then add headroom.
- Number of SIMs or numbers you need to operate. If you want separate numbers per branch, client or campaign, each needs its own channel, regardless of volume.
- Growth. Buying a larger chassis and leaving slots empty is cheaper than adding a second unit later, and it keeps everything on one host connection.
Our 8 vs 16 vs 32 vs 64 port comparison lays out the capacity, price and cost per channel for each model.
Using a GSM modem pool in the UK
Two things are specific to the UK: pools run on 2G here because 3G is switched off (use EE, Vodafone or O2 SIMs, not Three), and from 29 October 2026 a pool of five or more SIMs must be held for a good reason under the Crime and Policing Act 2026. Both are covered in GSM modem pools in the UK and lawful use and buyer verification; connection steps are in the USB setup guide.
Related terms you will see
SMS gateway and GSM SMS gateway describe a modem pool in use; see SMS gateway hardware. Multi-SIM gateway, multi-port GSM modem and multi-channel GSM modem are all synonyms for the same class of device; see multi-SIM SMS gateways. Bulk SMS modem is a marketing phrase for a pool sized for volume. And a 64 SIM modem or 64 channel GSM modem is the 64-port unit on this site.