As far as i understand it if you are in the UK texting a UK phone which is abroad, then it will come out of your normal allowances or free allowances because its still a UK number. For the person at the other end, texts received are free, they might only have to pay to send them or make calls whilst abroad.
So they can send you texts for free, It might cost you to return the texts though.
If you call from any EU country, Andorra, Croatia, Faroe Islands, Gibraltar, Iceland, Kosovo, Liechtenstein, Monaco, Montenegro, Norway, San Marino, Serbia, Switzerland, Vatican City.
*ROAMING DATA CHARGES CAN BUILD UP QUICKLY. IF YOU ARE CONCERNED ABOUT THIS WE RECOMMEND SETTING YOUR HANDSET NOT TO USE DATA WHILST ABROAD. MORE ON ROAMING SETTINGS.
|MAKING CALLS AND CALLING YOUR VOICEMAIL (CHARGED IN PER SECOND INCREMENTS AFTER THE FIRST 30 SECONDS)||35P|
|RECEIVING CALLS (CHARGED IN PER SECOND INCREMENTS)||11P|
|PICTURE MESSAGES (MMS) TO A UK MOBILE||16P|
|PICTURE MESSAGES (MMS) TO ANY OTHER MOBILE||24P|