Redspot IP telephony works in such a way that calls from you are transported over the Internet to our servers and from there on to the regular telephone network. You must therefore have an internet connection, but the other party must not.

You can thus call all regular telephone numbers and everyone can call you and that no matter where in the world you are without it costing you or those who call you extra.1 2

We believe that you should be free to choose how you want to make calls and thus freely choose equipment or app or a combination that suits your needs best. Learn more

Since most internet connections today are very good, you are free to choose which ever equipment or app you want to use as long as it supports SIP 2.0. 

For equipment we do recommend using well known brands like Cisco, Fanvil, Gigaset, Grandstream, Linksys, Polycom, Snom and Yealink since lesser known brands often aren't reliable enough because they have buggy firmware and don't put enough ressources into fixing the bugs.

The easiest and cheapest is to use an app on your smartphone or computer and there are a lot of different options. Most will work if they support SIP and are not locked to a provider. Learn more

For private use or a small business, we recommend the cordless IP phones in the Gigaset Go series that can be used with both IP telephony and ordinary analog telephony, can handle 2 simultaneous calls and can be extended with up to 6 handsets. Learn more If you require more functionality, Redspot's free cloud based PBX is a great choice. Learn more

If you have analogue telephones you are very happy with, you can use an analogue telephone adapter. If your internet connection is slow, it can be an advantage that the adapter has traffic prioritization (QoS) so that it can prioritize your call traffic higher and thus minimize interference. However, it only makes sense if all your traffic goes through the router and you do not f.x. use WiFi in the router you have from your ISP. Learn more

For business use, Redspot's free cloud based PBX is a great choice. Learn more

Can I use the IP telephony equipment I already have?

If you purchased your IP telephony equipment yourself, you can typically just change the setup and use it with Redspot. If your ISP has supllied your IP telephony equipment, it's only rarely possible - please consult your ISP.

No, Redspots plans are based on IP-telephony and thus don't use SIM cards. You will get a phone number and a password you will need for to enter into your App or physical IP-phone.

No, Redspot's current numbers are landline numbers and thus you cannot send and receive SMS.

Normally, moving your number takes a week from receiving your power of attorney and payment, but we can do it from weekday to weekday in urgent cases.

You usually have one month's notice with your current telecommunications company and must therefore be aware that you may be charged subscription fee until the end of your notice period. If you want us to move your number at a later date, please state this on the power of attorney or the email you send us the power of attorney with.

Note that you decide when your Redspot subscription starts, so if you f.x. currently are without internet connection, you can wait to activate your subscription until you have internet again.

Please notice

It may be necessary to first terminate various additional services, or split them up before it is possible to move a number:

• TDC Duet: Must be terminated / divided into 2 separate subscriptions first (mobile and landline.
• TDC "Nummerbestemt ringning" and "extra number" must be canceled first or moved together with the main number (requires extra number subscription). Contact us for more info.
• Extra numbers on ISDN must be moved together with the main number (requires extra number subscription) or terminated. Is it only an extra no. that is to be moved, it is possible if it is first changed to the main number and the extra numbers are then terminated. Contact us for more info.

You must be aware that you must not terminate your telephone number yourself and that you may be charged a fee by your current provider if you move the number before the end of the lock-in period.

You can use Redspot's IP telephony everywhere you have stable internet and it does not cost you or those who call you extra. No roaming charges. Ever!1

Note that a few countries and providers are blocking IP telephony including Belize, United Arab Emirates (Dubai, Abu Dhabi etc.), Oman (Muscat) and therefore a VPN is required to make IP-telephony work.

No, you can call all ordinary telephone numbers in the world and the other party does not have to have internet.

It costs the same as calling other Danish landline phones. It is free for Redspot IP-telephony customers to call each other.

Yes, if you have a analog landline, IP telephony or ISDN in a country where we supply telephone numbers.

Our subscriptions can be used on your smartphone, but as they require an internet connection, they cannot replace your mobile subscription.

Yes, you can either create a new subscription at that time or let the number replace your number with us.

Yes, you can make calls to anyone and receive calls from Redspot customers. If others call your number, your "old" phone will ring until the number is moved. Your IP-phone can though be called by using a small workaround. This may become relevant if you f.x. move from your current address before the number is ported.

If you have a good internet connection, there is typically no difference in the sound quality compared to ISDN and thus a far better than normal analogue landline as well as mobile calls.

In a comparison of IP telephony providers, the Danish leading newspaper Politiken named Redspot the best sound quality. As the conversation is moved over the internet, uptime and quality are always dependent on your internet service provider. Redspot's servers are located in a professionally monitored hosting center so downtime is minimized.

In 2020, Redspot's uptime was more than 99.999%.

Virtually all internet connections in developed countries are so good that they can be used with IP telephony without any problems. Try our test and learn more

Yes, they will just ring at the same time and this no matter where in the world they are. You can thus f.x. have an IP-phone at home, an adapter in the holiday home and an app on your smartphone or laptop when you are on the go.

Note, however, that there are limits to how many simultaneous calls you can have. Please refer to the product description and conditions for your subscription.

Yes, if your device or app supports this, some equipment supports even several simultaneous conversations.

Most of our subscriptions alllow 2 simultaneous calls, however note that 2 simultaneous calls require twice as much internet bandwidth (speed).

Between 30 and 90 kbit/s depending on the CODEC used. This corresponds to between 0.23 and 0.66 MByte/minute. In addition, there is a bit of traffic that the adapter / IP phone / app continuously generates to tell our server where you can be reached so that you can receive calls. Be aware of this if your internet connection is charged according to consumption.

Yes, if you use the G711 / alaw CODEC (standard in all adapters). However, it is also quite sensitive so your internet connection must be very good. In practice, it also depends on how good your fax is and it is impossible to say in advance how well it will work.

A CODEC is the the encoding IP-telephony calls are transmitted with. In general it can be said: The more kbps the better the sound quality. However, the sensitivity to interference also increases with higher kbps.

Both "ends" must support the desired CODEC. For IP-IP calls, such as between two Redspot customers, it is both adapters/ip phones/apps. For IP-PSTN calls such as to the ordinary telephone network including mobiles it is your adapter/IP telephone/app and our PSTN gateway.

Bandwidth requirements for various CODECs supported by Redspots PSTN Gateways