Choosing an Expat Tax Adviser: One Brain That Sees Both Countries

Updated August 2026 · 6 min read
The failure mode
Two halves

Two competent advisers, each optimising their own jurisdiction, can produce a worse answer than either would alone. The thing you are buying is somebody who sees the whole picture.

Need
Both sides
Check
Regulated
Ask for
Scope
Avoid
Guarantees

Most of what this site covers can be understood and acted on without paying anyone. A handful of things cannot, and they are concentrated in cross-border situations: equity vesting across a move, taking a pension lump sum abroad, corporate residence, and any estate planning involving two countries. In those cases the cost of advice is small relative to the size of the mistake.

The Structural Problem

UK accountants know UK tax. Local accountants know local tax. Neither is qualified in the other, and both will reasonably decline to advise on it. Left to themselves they optimise their own side, and the interaction — which is where the money is — goes unexamined. The workable arrangements are either one firm with genuine capability in both jurisdictions, or two advisers who will talk to each other with your consent and one of them owning the overall answer.

Ask directly: who is responsible for the interaction between the two systems? If the answer is nobody, or if both say the other will handle it, you do not yet have advice. You have two opinions.

What to Check

Warning Signs

SignWhy it matters
Approached you unsolicitedCross-border advice is a well-known channel for poor products
Advice bundled with a product saleThe recommendation and the commission are not independent
Guarantees a specific tax outcomeNobody can guarantee how another country will treat something
Pushes a pension transfer earlyA long history of expat pension mis-selling says slow down
Vague about regulation or feesBoth should be answerable immediately and in writing
Discourages a second opinionGood advice survives being checked

Prepare Before the First Meeting

  1. A timeline — departure date, job start, property completion, expected return if any.
  2. An asset list: pensions, investments, property, company shares, unvested equity, crypto.
  3. Your income picture in both countries for the year of the move.
  4. The specific questions you want answered, written down, so the meeting is not spent establishing facts.
  5. Your travel and workday records if residence is in issue — see proving non-residence.

An adviser given a clean set of facts produces better advice more cheaply. An adviser reconstructing your circumstances from a conversation charges you for the reconstruction.

What Advice Cannot Do

It cannot make an aggressive position safe, cannot bind a foreign tax authority, and cannot substitute for records you did not keep. It also cannot answer questions you have not asked — which is the strongest argument for reading enough of the ground to know what the questions are. That is what the rest of this section is for, and it is why the pages here explain mechanisms rather than promising outcomes.

Frequently Asked Questions

Do I need a UK adviser or one in my new country?

Usually both, or one firm with genuine capability in both. The critical point is that somebody owns the interaction between the two systems, because that is where the expensive mistakes live.

What should I check before engaging someone?

Regulation and professional body membership, professional indemnity cover, experience with your specific destination and income type, and a written engagement letter setting out scope and fees.

Is it a bad sign if an adviser approaches me?

It is a reason for caution. Unsolicited cross-border advice has a long association with commission-driven product sales, particularly pension transfers, so treat an approach as a prompt to check credentials rather than an opportunity.

How much should this cost?

It varies, but a fixed fee for a defined piece of work is usually better value than open-ended hourly billing for a one-off question. Ask for the scope and the fee in writing before starting.

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