After the major security breach they are using an 0870 number for contact. While it's possible that this is free from TT phones that's not good enough.
http://www.bbc.co.uk/news/technology-34615692On what's left of their website thare are plenty of other 0870 numbers. Sorry about mess of copy/paste text. Couldn't work out how to insert the image file that I'd made from a screenshot.
Sales Hotline       0800 049 7802       Mon - Thur  8am  - 10pm
Fri  8am  -   9pm
Sat - Sun  9am  -   8pm
Customer Services
& Technical Support       0870 444 1820
(FREE from your
TalkTalk landline)
or
0203 441 5550
(National rate number)      
Mon - Sun   24 hours a day
Newline Customer Services       0870 087 5703       Mon - Sun   8am  -   8pm
TalkTalk Mobile       0870 087 8751       Mon - Sun   8am  -   8pm
Cancelling a new order       0870 087 8038       Mon - Sun   8am  -   8pm