https://community.o2.co.uk/t5/Pay-Monthly/Bolt-on/m-p/1143569#M154573 Just don't change tariff after as you'll lose any data bolt on left happened to me before lol but if you used it all then it's ok Sun, 05 Aug 2018 02:16:41 GMT liggerz87 2018-08-05T02:16:41Z https://community.o2.co.uk/t5/Pay-Monthly/Bolt-on/m-p/1143392#M154503 Are 1off Bolt on carried over to next bill<BR /> Sat, 04 Aug 2018 11:44:28 GMT https://community.o2.co.uk/t5/Pay-Monthly/Bolt-on/m-p/1143392#M154503 Shadesbear 2018-08-04T11:44:28Z https://community.o2.co.uk/t5/Pay-Monthly/Bolt-on/m-p/1143394#M154504 <P>Yes, you pay for it on the next bill and any unused parts of the bolt on are carried over for 1 month also.&nbsp;</P> Sat, 04 Aug 2018 11:55:21 GMT https://community.o2.co.uk/t5/Pay-Monthly/Bolt-on/m-p/1143394#M154504 MI5 2018-08-04T11:55:21Z https://community.o2.co.uk/t5/Pay-Monthly/Bolt-on/m-p/1143569#M154573 Just don't change tariff after as you'll lose any data bolt on left happened to me before lol but if you used it all then it's ok Sun, 05 Aug 2018 02:16:41 GMT https://community.o2.co.uk/t5/Pay-Monthly/Bolt-on/m-p/1143569#M154573 liggerz87 2018-08-05T02:16:41Z