The money system

I spent the first six months assuming my new country's retirement savings scheme worked roughly like the one I'd left. It didn't — different contribution rules, different tax treatment, different access age. Nobody had lied to me. I'd just never checked, because it had a familiar-sounding name and I assumed familiar rules.

That's the trap with money systems abroad: the vocabulary sounds close enough that you stop asking questions, and the gaps are exactly where the mistakes live.

Tax residency — the question that changes everything else

Tax residency is usually not the same test as your visa status or how long you've physically been somewhere, and getting it wrong can mean double taxation, missed obligations in your old country, or missed obligations in your new one. Most countries have specific tests (days present, "permanent home," "centre of vital interests") and most have tax treaties with common origin countries designed to prevent you being taxed twice on the same income. This is worth a paid consultation with a cross-border tax accountant in your first few months — genuinely one of the highest-value calls you'll make, because the cost of getting it wrong compounds for years.

Retirement savings — same idea, different rules everywhere

Superannuation (Australia), a 401k (US), KiwiSaver (NZ), a workplace pension (UK) — these all do roughly the same job but with different contribution caps, different tax treatment, different preservation ages, and different rules about what happens to money you built up in your previous country. Some countries let you transfer prior retirement savings in; others don't, or only under specific conditions. Find out explicitly rather than assuming continuity — this is not a "figure it out eventually" item, because contribution and transfer windows can close.

Banking and credit — starting from zero

Your credit history usually doesn't transfer between countries. That "excellent" rating you built over fifteen years at home can mean nothing to a bank or lender in your new country, which can affect getting a credit card, a phone plan, or a rental without a large deposit. Ask directly whether any credit-building product exists for new arrivals (a secured credit card, a specific new-migrant product) rather than assuming you'll be treated as high-risk forever — most banks in most developed countries have a pathway, it's just not advertised loudly.

Currency exposure

If you're still earning, owed money, or holding savings in your old currency, understand what that exposure actually costs you in fees and exchange rate movement, particularly for regular transfers (rent back home, remittances to family, an old mortgage). A dedicated transfer service is usually meaningfully cheaper than a standard bank transfer for anything recurring — worth setting up properly rather than accepting whatever rate your bank defaults to.

The one call worth making early

Of everything in this module, the highest-leverage single action is a paid session with a cross-border or migrant-specialist accountant in your first three months — not your old accountant, not a generalist, specifically someone who handles people moving between your two countries. The fee is small against the cost of a tax residency mistake compounding for years before anyone notices.