How do extensions of a Croatian stay and work permit work?

If you are continuing in the same role with the same employer, the extension process is more streamlined than a first application because a new labour market test is normally not needed.

You should apply before your current permit expires and ensure the underlying conditions, such as ongoing employment and paid contributions, still hold. If you are changing employer or role at the same time, that is treated as a new permit situation rather than a simple extension, so plan timing accordingly.