If you manage the apostille of your Certificate of Residency on your own by mail, it may take 2-5 weeks, and can take longer. It will need to go to the appropriate apostille office that holds jurisdiction over where your document was issued and/or notarized.
If the document is destined for a non-apostille country, there will be an additional step of legalization. The final step of legalization can take anywhere from 1 day to a few weeks depending on the diplomatic mission.
If there are any errors in the preparation of the Certificate of Residency (or the supporting documents for embassies), your document will likely be returned unprocessed.
Contact an IDC expert for a more detailed estimate of how long it will take if we handle the apostille of your Certificate of Residency on your behalf.