I have tried to call 0844 prefix and 0845 prefix telephone number in the UK on both Mobile (AIS) and landline (TOT) but all numbers rejected.

I vaguely understand that some providers will not permit connection to these numbers but can anyone give me a simple explanation?

Can the prefix of the numbers be modfied to make an accessible number?

If you keyed the 0 (zero) in, then you wouldn't get a connection.

The 0 is for use within the country.

For international calls you leave the zero out.

Example +44 (0) 123 4567 means -

+ international dialling numbers (depends on which country you are in and sometimes which country you are calling and whether cheap rates are available);

44 the UK international dialling code

(0) do not use for international calls

123 4567 the phone number you are calling (probably a lot longer since the days I was there)

Even if you get the prefix correct, some overseas phone providers will still not let you dial UK 0845 or 0870 numbers, or will charge an arm and a leg if you do. Also some UK companies restrict incoming access to these numbers to UK callers only.

The answer, of course, is http://www.saynoto0870.com/

Thanks. I am well aware that the initial zero needs to be dropped and that the UK code is '44'. The bank that I was trying to contact show the numbers to ring from outside UK as 0844 and 0845 prefix that I could not access via my mobile or landline. Possibly if I had dialled the prefix to connect through CAT on my landline it would have connected but that means having to go to my local CAT office at the end of the month to pay their charge whereas my ToT account is paid through DD.

Fortunately, I found an alternate number and was able to transact my business.

Use Skype it may work. I have used Vyke IP phone and that works for these numbers.

0845 numbers always work on 1-2call mobiles and Skype, but never on TOT landlines (for me). Some other premium numbers are blocked by TOT and 1-2call (which is also TOT I think) - for instance my Orange voicemail number. I did try to get an explanation form TOT but was referrred to my local area office who simply put up a straight bat - 'sorry - not permitted'.

Last time I measured it (about one year ago) call rates for 0845 were about 10p a minute on Skype and 20p a minute on 1-2call mobiles.

Some time ago I made a point of scouring the websites of the financial institutions I normally deal with (I deal with a lot as I look after the finances of several older family members as well as myself) and recording and using the non-premium numbers that most such institutions now provide. For those I could not find, if I did have to call an 0845 call centre my first question was 'I'm in Thailand, what non-premium number can I call you again from'. It cuts the call cost in thirds roughly compared to the regular 0845.