Is it safe to pay bills over satellite internet?
Satellite is not safe. Neither is cell data, wifi, or cable Internet. None of it is safe at the layer that you are talking. And that's not the layer that needs to be safe.
It's the data that goes over satellite (or wifi, cell, or cable modems) that needs to be secured. That's why we have HTTPS, that little green lock on your browser (it's gone now on most browsers and just grey now because HTTPS is pretty much everywhere).
So your choice of internet provider's media is not what's important in your situation. It's whether you use encrypted sites over that media.
I would like to specifically address the question on why security of the underlying mode of communication is not as important as the encryption of the message.
You are communicating with your bank to request a transfer from one account to another. You might write a letter something like this, using an official form you picked up from the bank.
Dear Bank Manager at Acme Bank, Local Branch, 123 Fake St, My Town, USA Please transfer $1 from Account 00000 to Account 00001, signed me.
On the Internet, HTTPS and TLS, as described by simon and schroeder will take this message and transform it into something that only you and the bank can read (Among other technical things, including verifying your identity and message integrity like an old fashioned wax seal).
Perhaps your message becomes something like this (just an example)
This message will now need to be sent to the bank via post (Internet).
Now you might have 3 choices.
- Walk into the post office and shout the message at the top of your lungs so the postmaster (and everyone else) can hear it
- Put it in an envelope (Address visible!) and hand it to the postal carrier that is going door to door every morning
- Send an armored car to deliver directly to the local post office.
All 3 will have different ways of being listened on or intercepted. All are insecure in their own way, since you rely on others to carry the letter. However, since the message itself is secure, you do not care.
Unlike sending physical mail, the message itself has no value, if it is lost or "stolen" you will just send it again, so an armored car is just extra expense and hassle, you only care if someone can read it, or can pretend to be you or the bank.
It is best to protect the message, and not rely on security of the method of transfer.
The physical support you use to transport the information doesn't make it more or less secure. Communications nowadays are all encrypted using protocols such as TLS. This means that the information cannot be read by anyone else than the receiver. You might want to read a little about Encryption.
Now while these protocols exists, it doesn't mean that everyone use them. While handling sensitive data, you have to verify yourself that they do. If you have doubts, you can probably contact your service providers for more information.