Practical differences I've run into:
- Leverage. The obvious one. 1:30 on majors under ESMA rules versus 1:500 or more offshore.
- Client money protection. Onshore entities usually have segregation rules and a compensation scheme. Offshore protection is often just a line in the terms.
- Negative balance protection. Mandatory for retail in the EU and UK. Offshore it may be offered as policy, which can change.
- Dispute route. With an onshore entity you can go to an ombudsman or regulator. Offshore you mostly have the broker's own complaints form.
- Withdrawal speed. In my experience not much different, but when it goes wrong, the onshore route gives you more leverage of the useful kind.
Which entity are you on, and was it a deliberate choice or just the default during sign-up?