Buying a prepaid SIM card should be one of the easiest things you do after arriving in a new country.
In Brazil, it turned into one of the most frustrating experiences of my trip.
I was staying in São Paulo and went to official mobile-phone stores around Avenida Paulista, assuming that buying a local SIM directly from an official carrier would be the safest and simplest option.
I was wrong.
The Problem: No CPF
In Brazil, many everyday services revolve around the CPF, the Brazilian individual taxpayer identification number.
As a foreign tourist, I didn't have one.
When I explained that I was a foreigner and wanted a simple prepaid SIM card with mobile internet, instead of offering me the normal inexpensive prepaid option, I was told about a supposedly "special plan for foreigners."
The price?
Around US$100.
For a SIM card and mobile data.
At first, I thought perhaps this was simply how the system worked for tourists. After all, I was inside an official store on Avenida Paulista, not dealing with somebody on the street.
But something didn't feel right.
The Same Thing Costs Less Than $10
Later, I found small kiosks selling prepaid SIM cards.
The difference was almost ridiculous.
With a CPF, a SIM card and prepaid package could cost less than US$10.
So we were talking about roughly:
- Official-store "foreigner" option: about US$100
- Normal prepaid SIM: less than US$10
The biggest obstacle wasn't actually buying the SIM.
It was the CPF.
Speaking Portuguese Saved Me
This is where knowing some Portuguese completely changed the situation.
I was able to explain what had happened and ask local people for help.
They understood the problem immediately.
Instead of trying to sell me an expensive tourist package, they actually helped me activate the normal prepaid SIM by allowing their CPF to be used for the registration.
And suddenly, the impossible became simple.
I had a working Brazilian SIM card for a fraction of what I had been asked to pay in the official stores.
The people who helped me were incredibly kind, and that part of the experience actually left me with a very positive impression of Brazilians themselves.
The frustrating part wasn't the people.
It was the system — and the way being a foreigner unfamiliar with the CPF requirement made me an easy target for an extremely expensive offer.
A Warning for Tourists Visiting Brazil in 2026
If you're traveling to Brazil and need mobile internet, don't automatically assume that walking into a large official store will get you the best deal.
Before agreeing to an expensive "foreigner" or "tourist" plan, find out what the equivalent normal prepaid package costs for Brazilians.
The difference can be enormous.
Also, learn a few basic sentences in Portuguese before arriving. Even a little Portuguese can make a huge difference when you're trying to understand prices, registration requirements, and whether you're actually being offered a normal product.
My experience in São Paulo went from a proposed US$100 SIM card to one costing under US$10, simply because I understood what was happening and found people willing to help me navigate the CPF requirement.
Brazil is an amazing country, and the ordinary people I met were helpful and welcoming.
But buying a SIM card as a foreigner?
That was a nightmare.
