How can an NRI or OCI holder get Indian citizenship if their spouse is from India

Another important point is that India generally does not allow an adult to simply keep a foreign citizenship after acquiring Indian citizenship.

The Citizenship Rules for registration through marriage require an undertaking concerning renunciation of the applicant's existing citizenship if the Indian application is sanctioned.

That's particularly important for someone currently holding a US, UK, Canadian or Australian passport.

I would therefore treat this as two separate decisions:

1. Whether you qualify for Indian citizenship by registration through marriage.
2. What happens to your existing citizenship and passport if Indian citizenship is granted.

If you're already an OCI holder, don't assume that your OCI automatically converts into citizenship. Section 5 also has a separate route for certain OCI cardholders who have held OCI registration for five years and are ordinarily resident in India for twelve months immediately before applying.

The exact route can therefore depend on your circumstances.

I looked into this because my spouse is Indian too.

One thing that confused me initially was the difference between OCI and citizenship. An OCI card doesn't make someone an Indian citizen. It provides certain rights and immigration benefits, but the person remains a foreign citizen.

For citizenship through marriage, Section 5(1)(c) specifically refers to a person married to an Indian citizen who is ordinarily resident in India for seven years before applying. The Act also explains how "ordinarily resident" is calculated for this category.

So if you're living in the US, UK, Canada or elsewhere and only visiting India occasionally, I wouldn't assume those visits satisfy the same requirement as being ordinarily resident in India.

I'd also be careful about older forum posts because citizenship and OCI rules can be amended. The Ministry of Home Affairs maintains the current citizenship and OCI information.

Marriage to an Indian citizen can provide a route to Indian citizenship, but it isn't automatic.

Section 5(1)(c) of the Citizenship Act allows a person married to an Indian citizen to apply for registration as an Indian citizen if the person is ordinarily resident in India for the required period. The Act specifies seven years.

The Citizenship Rules state that the application is made on Form III and that the applicant must satisfy the applicable residence requirement and take the required oath. They also state that the applicant gives an undertaking regarding renunciation of their existing citizenship if the Indian citizenship application is approved.

So I wouldn't treat an Indian marriage certificate by itself as enough.

If you're currently living abroad, I'd first look carefully at the residence requirement before making plans around citizenship. The exact calculation can matter, especially if you've spent significant periods outside India.