So... If I'm getting this right, having a real SIN gets you taxed, but having a fake SIN does not and this doesn't generate suspicion.

What if you're dual SINned (EG national (Aztlan) plus limited corporate (Aztechnology))? do you have to pay 35% of your income in tax? Again, why do fake SINs not incur tax?

OMG, I've been playing an elven Fiona, named Felicia, all this time and nobody told me.

Even if all that credsticks are are glorified 20th century debit cards, those prepaid cards we use even today have fees that get directly subtracted from the money in them.

I can imagine certified credsticks would work without a SIN,Ootherwise what would the SINless use for money? For taxation purposes, hat raises the problem as to what rate to tax and possibly as to who receives the money (SIN issuing authority, nation, corp). In that case, those kinds of credsticks probably work much like you describe. Trying to tax them at variable rates (or at all) is probably a bad idea.

My thought was to not tax them at all when they change hands, but to possibly charge income tax when nuyen goes to some account attached to a SINner. There could even be a default rate for transferring money between "SINless" devices (who would be entitled to this money?), but the more I think about it, the act of actually certifying a credstick is probably much more involved than simply an encrypted money transfer, thus the device receiving the money wouldn't be certified, and thus not as much like cash, annnd... possibly subject to taxation. (Here we go again.)

Maybe this level of detail is too much for the majority of players.

I find it interesting how a lot of roleplayers tend to relisticicise themselves out of games. There are obvious logic holes in how credsticks work. In the earlier editions of Shadowrun they used to just pull the 'It just works' card out and everyone seemed fine with it. When it came to phone usage they basically just said "there are ways the shadowrunners can call their contacts or other people and not have the calls traced". It didn't really explain it, it just worked.

Here's how I deal with credstick realism:

Q) What's a credstick?
A) It's literally an electronic wallet. You can transfer money from one to another just like pulling cash from one wallet and putting it in another.

Q) Wait, can that be hacked?
A) No

Q) Why not?
A) Because.

Q) How do I secure my money? I don't want to walk around with thousands on me.
A) You transfer it into an account.

Q) (Dumb questions about account realism)
A) /snore

A credstick CAN be hacked in 4th ed... but... well... hacking credsticks is more about putting money ON than taking money OFF.

Only if you assume they are wireless enabled. And yes, it is generally more about creating fake money than it is taking someone else's money. Easier way is to just take control of the reader and give a false validation of funds, "Spoofing" the payment as it were. SO much easier than creating fake money.

Only if you assume they are wireless enabled.

Well now you're just lacking in imagination. If you know in advance a device the credstick will be inserted into, you can hack into that and get the credstick when it gets plugged in. Wireless isn't the only option for hacking, it's jsut the only one without varying prerequisites.