Budget 2017: Cost of mobile roaming outside the EU set to rise

!The article quotes Mr Hammond thus:

In his Budget speech this afternoon, Chancellor Philip Hammond said the Government plans to roll out measures that will "introduce UK VAT on roaming telecoms outside the EU in line with international standard practice".

I think he is making a possibly incorrect statement there.

From Wikipedia

In order to avoid double taxation, non-taxation or the distortion of competition, an EU member state may, in accordance with Article 9(3)(a) of Council Directive 77/388 ("the Sixth VAT Directive"), include within the scope of its national VAT any telecommunications services used within its territory but billed outside the EU VAT area. When opting to do so, it must also exempt from its national VAT any roaming services supplied by home networks within its territory but used outside the EU VAT area. The inclusion of telecommunications within the scope of Article 9 was requested by the United Kingdom,[26] which subsequently enacted the change under Article 19 of the Value Added Tax (Place of Supply of Services) Order 1992. Consequently, when an EU member state makes this VAT exemption, roaming on networks in the Åland Islands, Gibraltar, Iceland, Liechtenstein, Norway, the Canary Islands, Ceuta, Melilla and French overseas departments is subject to the price caps with no VAT applied, because these countries and territories are within the EEA but outside the EU VAT area.

That can be read as if it also applies to countries geographically outside the EU

I just looked at and translated a couple of pages about German customers roaming outside the EU. In theory regulations provide that use outside the EU is not subject to MwSt (VAT).

Maybe each EU country has some discretion about how it applies the rules, and that is what Mr Hammond is relying on.

I also looked up 4 other random countries

Customers of mobile networks of Australia Malaysia New Zealand and Singapore do not suffer GST on their roaming fees.

Maybe Mr Hammond is making some changes as if we had already left the EU, but reciprocal arrangements for taxation of roaming fees from EU customers coming here and us going abroad will surely be amongst the negotiations that will occur soon, and we don't want to end up with double taxation. We may be in or not in the Single Market, but are they going to dump international tax arrangements with the EU and with other non-EU countries?

Whatever happens in those negotiations, his declaration that this is international standard practice is untrue for all of the first 5 countries I looked up.

All non-EU roaming charges can be avoided by using a dual-SIM phone, with your UK network SIM in one slot and a local SIM from a network in the country you are visiting in the other.

Any SMS can be replied to directly, selecting SIM2 to send it. Instead of answering an incoming call to SIM1 (UK SIM), refuse it and call back using SIM2. Call and SMS costs vary widely according to country etc, but in the vast majority of cases it will be cheaper to do this than pay the outrageous roaming charges. A data package on the local SIM will usually be relatively cheap also.

The same can be done by carrying two handsets of course, but much less convenient when you cannot respond directly to the number calling and have to type it in to the other phone.

I've not used a single SIM phone since well before the advent of smartphones, nor paid any non-EU roaming charges.