Phone
Country calling code for Bosnia and Herzegovina is +387. Buying a SIM card is pretty simple, but you need a mobile phone which is not locked. Most SIM cards can be purchased at news stands or specialised shops, they cost around 5 euros and you get some credit. You can top it up at the same place that you bought the SIM card, but also at supermarkets and some ATMs.
There are 3 main providers:
HT EroNet (063, 064)
M-Tel (065, 066)
Bosnia and Herzegovina is not in the EU, so it might cost more to make international calls because roaming fees still apply.
Post
herzegovina.travel/blog
There are two post offices in Medjugorje:
1) The one on the corner of Dr. Franje Tudjmana is open:
Mon – Fri: 7 a.m. – 4 p.m.
Saturday: 7 a.m. – 12 p.m.
Sunday: closed
Phone: +387 36 651-990
2) The one next to the church is open:
Mon – Sun: 8 a.m. – 8 p.m.
Internet
Most restaurants, hotels and cafés have free WiFi, so you can ask staff for the password.
If you’ve purchased a SIM card and you have a smartphone, you can also activate a tariff which includes mobile Internet (if you need it on the go). Most of the tariffs include 250, 500 or 1,000 MB, which should be enough for a day or two.