Pay as you go services are good option if you stay short term, but you can consider contract plans if you are staying for more than 2 years.
How to get a Hungarian SIM-card
There are three main network operators in Hungary: Telekom, Vodafone, Yettel.
Each provider offers multiple packages and affordable rates. The providers usually have shops in big shopping malls or in the city center.
Two examples of a SIM-card offer
Pay as you go plans: credit is purchased before using your phone, once your credit runs out you cannot use the mobile services. To use it again, you can top up your credit online or in stores.
Contract plans: each month you pay a fix fee to use your phone.
Prices usually vary between 30-50 HUF per minute or per SMS if you have a pay as you go plan. In case of contracts even the most basic packages include 3-4 GB internet data per month, and there are packages with unlimited calls and data. Same goes for calls, number of minutes range from 100 minutes to unlimited in the different sized and prized packages. You can usually use your data within the EU with the same conditions as in Hungary, and if you have unlimited data you can even use some data (with Telekom at the moment monthly 2GB) anywhere in the world.
What you will need as a foreigner
As a foreigner for a contract you will need passport and proof of accommodation (for example rental contract).