The best is to buy a local operator TIGO phone card at a little shop for 1000 to 3000 tzs (1€ = +- 2500Tsh)

You can buy "Air time" crédit at the little shops to transfer crédit directly on your new sim card. 

Do not call or do not surf on internet directly with your airtime crédit because its too expensive. You should buy packs.

To buy a pack to call all tanzanians operators, you should enter: *148*00#  (then call) - 3.minikabang - 3.Monthly - 2.19999Tsh=330min+2000SMS+200MBinternet - 1. to accept

and to buy an internet pack *148*00# - 5.Internet Packs - 1.Internet Packs (NEW) - 3.Monthly - 3.15GB @ 35,000Tsh - 1.Main Balance to valid

If you want to check your airtime balance you should call the  *102*#  (the best is to let the minimum airtime balance because when your packs are empty the calls and the internet connection are dirrectly invoiced on your Airtime credit, and it is very expensive)

For the internet pack balance call the *102*02#

For the calls pack balance, call the *102*01#

Karibu Tanzania