This is a common question we receive, especially when the applicant's birth country is subject to long backlogs. 

Generally, the visa bulletin's rule is that you must use your country of birth. This means that if you were born in China but are now a Canadian citizen, you are still subject to the China priority dates.  

There are exceptions to this general rule that may benefit an applicant.

• Cross-Chargeability to your Spouse -  9 FAM 503.2-4(A)(h)

You can be counted against the birth country of your spouse if that country has favorable wait times. 

For example, an applicant with an EB-2 petition who was born in India but is married to someone with a birth country of France would be able to use the “All Chargeability Areas Except Those Listed” priority dates. 

•  Birth in a Dependent Area - 9 FAM 503.2-2 

If you were born in a dependent area (a territory that does not possess full political independence or sovereignty as a sovereign state) can be charged to either the dependent area or the mother country. 

• Preventing Separation of Families - 9 FAM 503.2-4(A)(a)

Your spouse or child may be charged to your country of chargeability to prevent family separation, if an immigrant visa would not be immediately available if they were charged to their own country of birth and they are accompanying or following to join you. 

• Applicant's Place of Birth is Not Parents' Country of Birth or Residence - 9 FAM 503.2-4(C)

Children born when the parent or parents were stationed in a third country under orders or instructions of an employer, principal, or superior authority whose business or profession was foreign to that foreign state, the applicant may be charged to the foreign state of either parent.  This also applies to those born on the high seas.