The 30-year-old actor debuted on the site with a selfie taken on a cruise. Sidharth is currently holidaying with his family.
"Opening selfie...No longer a Instagram Virgin," he captioned the picture.
Sidharth is available with the Instagram handle s1dofficial.
The "Student of The Year" star will be next seen alongside Akshay Kumar in "Brothers".
Other Bollywood stars who are on Instagram include Varun Dhawan, Alia Bhatt and Priyanka Chopra among others.