company moved to different address do I need to fill in all bank details again

Only the address field changes, the rest of the file remains unchanged

No, after moving you do not fill out the entire bank questionnaire again. An address change affects exactly one piece of information: the establishment address of the company. All other answers in the chain file — size, sector, certificates, insurance — remain valid and do not need to go through the source again.

What does often come into play: banks request the address as it appears in the Trade Register, and sometimes want to see a recent extract as proof. Once the Chamber of Commerce registration has been updated, that extract is the document with which you support the new address. Also check at that time whether the company's registration number still appears correctly in the file — a move sometimes coincides with a change of establishment type, and then more changes than just the street name. If the legal form and the Chamber of Commerce number remain unchanged, updating that one field is sufficient.

Where this follows from: Trade Register Act 2007

The establishment address is one of the particulars registered under the Trade Register Act 2007 for every enterprise, and any change to it must be notified to the Trade Register. For the bank, that registered address is the authoritative information: they usually check against the Chamber of Commerce registration, not against what was in an old PDF form. Once the Trade Register shows the new address, that is the source with which the answer in the file is updated — the rest of the questionnaire remains untouched, because it is based on other information.