1 Paris: Okay, so we need to buy an upgrade for the nano-goo software.
2 Paris: Just do it and let’s get that hyperdrive repaired!
3 Paris: Surely we have enough in our cargo business account.
4 Serron: Yeah, about that...

If you imagine a science fiction setting with faster-than-light travel, but no FTL radio or other communication, then the quickest way to send information anywhere is to take it physically. Then think about what this means for banking. You can't open an account on one world, deposit money, take an FTL trip to another world, and expect the bank branch there to have your money, or even know that you have an account with them.

When you travel FTL, you're going to have to convert your bank account to physical valuables like gold or whatever, and carry it with you to the next world. That could be a very interesting detail in a story.

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Reader Jeff A. writes:

There are definitely ways around this problem, including cryptographically signed physical tokens, akin to modern HSM (Hardware Security Modules).

And Alec C. writes:

It is not true that you always have to take valuables with you, if the route is well travelled even if the fastest way to travel is in person. This was solved in Europe by the concept of correspondent banks. A bank in London would have a correspondent bank in, say, Vienna. They should give you a letter that said, effectively, “please give the bearer, D Morgan Mar, the equivalent of 100 gold coins in your currency”. And the same would happen in reverse, when someone travelled from Vienna to London. The concept which later became travellers cheques. In principle, the two flows of currency would net out and no gold need travel. And, of course, the commissions involved would be substantial. The trust involved, of course, is massive. Both ends involved need to trust that the other will keep good accounts. For this reason, such transactions were dominated by Jews. Not because of any inherent greater honesty, but because Jews could identify themselves to other Jews by their detailed knowledge of Jewish laws and customs (and, for men, a quick check in the underwear). The cost to a Jew of being expelled from the Jewish community, both emotionally and physically, was too high to risk. Hence Jews became the people wealthy travellers would have to deal with, and would detest because of the aforesaid substantial commissions (on top of racism and religious bigotry).