This is the question every adviser asks first and the one a website is least qualified to answer. Here is the shape of it, and where you have to stop reading and call someone.
Nothing here is legal advice. What you can take is determined by your employment agreement, your firm's participation in any broker protocol, and the law of your state. Those documents differ enormously and the differences are the whole answer.
Have a lawyer who does this specific work read your actual paperwork before you do anything, including telling a colleague.
Client relationships are, in practice, portable more often than firms would like. Client data is usually not. The distinction is between a relationship and a record.
Where a protocol applies, it typically permits a departing adviser to take limited contact information for clients they served. Where it does not, the position is governed entirely by contract.
This is the one that catches people. A track record generated while employed generally belongs to the firm where it was generated, and cannot simply be carried over and presented as your own.
An adviser with fifteen years of history can find themselves marketing a firm with no history at all. That is a genuine commercial gap and it needs planning for rather than discovering.
You may leave with your clients and without your numbers. Those are different assets and only one of them is usually yours.
What you know. Your judgement, your process, your understanding of the clients, and your professional relationships are not the firm's property.
That is more than it sounds. It is most of what the client is actually buying.
What you do before resigning is scrutinised far more closely than what you do after. Preparation that involves firm resources or client data is where otherwise reasonable people create real legal exposure.
You cannot pre-warn clients, and it will feel dishonest not to. It is not. Your obligations run to your employer until the day you leave, and clients you have served well will understand the constraint you were under.
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