UK fans of free SMS service should take advantage of the service as much as they can because mobile phone companies are rethinking about their plans that allow users to send SMS without any charge.

As prices begin to rise, some mobile companies have started to give a limit to the number of free short text messages people can send.

Free messaging facility is expected to vanish completely with changes in tariff structure due in February.

To deal with short text messages, UK's mobile phone companies are changing the way they charge each other. So far, they were charging each other by the quantity of messages, but with the rising popularity of messages, they are now compelled to charge 3p per message.

The key players of UK's biggest mobile phone companies expect that these costs will balance out among them as they have almost equal number of subscribers.

However, these changes are adversely affecting companies that direct free SMS messages from UK mobile users to other Uk users through foreign networks.

The cost of a standard SMS message across Europe is same but they are not the same for bulk messages. The cost varies between 1.5 and 7.5 US cents if you send SMS across the GSM network in Europe.

As Switzerland, Germany and Italy are the lowest cost networks, so to reduce costs, many of the free SMS services are routed through these countries.

With the SMS charges going 3p per message, all this will change. It is doubtful that UK mobile users are going to send text messages to Germany and Switzerland. If this happens, these mobile phone networks are going to have to pay very heavy bills. Talks are on between free SMS providers and potential partners that could provide some profits so that the cost of providing the free messaging service is compensated.

Several companies are rethinking about their free SMS service and are limiting their users to a particular number of messages per day.

Buckingham of mobile lifestreams consultancy said that the changes in charges were expected because phone networks are being flooded with SMSs. These changes would affect the survival of many free SMS services.

Will the phone networks work out some plan to offset the cost of free SMSs or is this the end of free SMSs, is something that still remains to be seen.