In short: VoIP DECT phones are cordless handsets that connect by radio to one or more base stations, which link to your cloud or on-site phone system over the data network. Single-base systems suit small premises; multi-cell systems hand calls between bases across large sites. They suit warehouses, schools, surgeries, shops and hotels.
How IP DECT works
DECT (Digital Enhanced Cordless Telecommunications) is the radio standard behind most cordless phones. In an IP DECT system, the handsets talk by radio to a base station, and the base station connects to your network and registers each handset with the phone system as a SIP extension. To the phone system, a DECT handset is just another phone with its own extension and number.
DECT uses its own frequency band, separate from Wi-Fi, so cordless calls do not compete with laptops and tablets for wireless capacity. That is one reason many organisations choose DECT over Wi-Fi handsets for staff who are on the phone a lot.
Base stations are usually powered by Power over Ethernet (PoE) from a network switch, so each one needs a network cable but not a mains socket. Put the switch on battery back-up if handsets must keep working in a power cut.
Single-cell, repeaters and multi-cell systems
| Set-up | How it works | Suits |
|---|---|---|
| Single-cell | One base station covers the area and supports a limited number of handsets and simultaneous calls | Small offices, shops, single-floor surgeries |
| Single-cell with repeaters | Repeaters extend the radio coverage of one base without extra network cabling | Awkward corners, an extra room or a yard |
| Multi-cell | Several base stations work as one system; a call hands over from one base to the next as the user walks, without dropping | Warehouses, schools, care homes, hotels, multi-storey buildings |
The number of handsets and simultaneous calls each base supports varies by manufacturer, so the design is driven by both coverage and call volume. A busy area such as a dispatch office may need more base capacity than a quiet corridor, even if one base could reach both.
Rugged, alarm and specialist handsets
Handsets range from simple office models to devices built for harder environments:
- Ruggedised handsets with dust and water resistance for warehouses, kitchens, workshops and outdoor areas
- Alarm handsets with an emergency button and, on some models, man-down or no-movement alerts for lone workers, site staff and care settings
- Handsets with messaging that can receive text alerts, for example from a nurse-call or building system, where the DECT system supports it
- Headset-ready handsets for staff who need both hands free
- Chargers and spare batteries for shift work, so a handset is always ready
Battery life depends on the handset, the battery's age and how much time is spent on calls. Plan for a charging routine and spare batteries on sites that run long shifts rather than relying on one charge per day.
Site surveys and coverage
Walls, steel shelving, lift shafts, glass and machinery all affect radio coverage. For anything larger than a small office, a site survey is the reliable way to plan base station positions:
- Agree the areas that must have coverage, including stairwells, car parks, yards and outbuildings
- Measure signal on site with test equipment, rather than estimating from a floor plan
- Mark base station and repeater positions, and check each has network cabling and PoE
- Size the system for busy areas and simultaneous calls, not only for coverage
- Re-test after installation and after any major building change
Schools are a common example: site staff, caretakers and senior leaders need to be reachable across buildings and playgrounds. Our school phone systems page covers that in more detail.
Compatibility with 3CX, Teams and hosted platforms
DECT systems register handsets as SIP extensions, so compatibility is about the base station and the platform:
- 3CX publishes a list of supported phones that includes DECT systems from several manufacturers, some of which 3CX can provision automatically. See hosted 3CX.
- Microsoft Teams Phone connects compatible IP DECT systems through Microsoft's SIP Gateway, which lists IP DECT base stations, servers and handsets from several manufacturers. Each user needs a phone number with PSTN calling enabled. A Session Border Controller with Direct Routing is another route.
- Hosted platforms such as Forever UC and Webex Calling support SIP devices; we confirm the specific DECT system before you order.
If you already have a DECT system, it may be possible to keep it when you change phone system. Check whether the base stations are still supported by their manufacturer and appear on the new platform's compatibility list.
How we help
We survey the site, design the base station layout, supply handsets suited to each role and connect the system to your chosen platform. Prices depend on the size of the site and the handsets you need, so ask us for a quote.
For desk phones, conference phones and headsets, see VoIP phones and handset types. To plan a cordless system, contact us with a floor plan and the areas you need covered.
Why choose your cloud phone system with Forever Systems
We are vendor-neutral. Forever Group supplies and supports several cloud phone platforms, so we recommend the one that fits how your organisation works rather than the one we happen to sell.
- Side-by-side comparison of hosted 3CX, Microsoft Teams Phone, Forever UC, Forever Teams and Webex Calling for your users
- Contact centre and call recording options matched to your call volumes and CRM
- Number porting, handsets and set-up handled for you, including the move off analogue and ISDN lines
- Connectivity checked so call quality is right from day one
- UK support for moves, adds, changes and faults
- For BT Cloud Voice, see our BT Business Partner site cloudvoice.cloud
We work with businesses, schools, charities and public sector organisations. We do not sell consumer phone services.
Want a vendor-neutral cloud phone system comparison and quote?
Tell Forever Systems what you need and we will come back to you by email with options, not a hard sell.
Contact usFrequently asked questions
What is an IP DECT phone?
An IP DECT phone is a cordless handset that connects by radio to a DECT base station, which connects to your phone system over the data network. The handset gets its own extension and number, just like a desk phone.
Is DECT better than Wi-Fi for cordless phones?
For many sites, yes. DECT uses its own radio band, so calls do not compete with Wi-Fi traffic and coverage can be planned just for voice. Wi-Fi handsets can make sense where the wireless network is already designed for voice.
Do DECT phones work with Microsoft Teams?
Some do. Microsoft's SIP Gateway supports compatible IP DECT systems from several manufacturers, and each user needs a phone number with PSTN calling enabled. A Session Border Controller with Direct Routing is another option.
How many base stations do I need?
It depends on the building and the number of simultaneous calls, not just floor area. Walls, shelving and machinery affect coverage, so a site survey with test equipment is the reliable way to decide.
Can I keep my existing DECT system when I change phone system?
Often, if the base stations are still supported by their manufacturer and are compatible with the new platform. We check the system against the platform's compatibility list before you commit.