GST registration not only helps you in getting your business recognized as a legal registrant but also opens a number of opportunities for your business. Benefits to GST registered business at glance are as follows: -

Become more competitive – You will be more competitive in comparison to your unregistered competitors since you will carry valid tax registration.
Expand your business Online – You cannot sell products or services on e-commerce platform without GST registration. If you're planning to give a blow on e-commerce platform like Flipkart, Amazon, Paytm, Shopify or through your own website, you must need a GSTIN.
Can take input tax credit – Only Registered GST holders can avail input of GST tax paid on their purchases and save the cost.
Can sell all over India without any restrictions – Without having GSTIN you cannot trade inter-state. This is possible only if you registered your business under GST.
Apply Government Tenders – Various government tenders requires GSTIN to apply tender.
Open Current Bank Account – Especially, in case of sole proprietor business Banks & Financial Institution does not open a current bank account in the name of business trade name unless you carry any government proof in the name of your business.

Some important facts:

Registration of any business entity under the GST Law implies obtaining a unique number from the concerned tax authorities for the purpose of collecting tax on behalf of the government and to avail Input Tax Credit (ITC) for the taxes paid on his inward supplies.
Without registration, a person can neither collect tax from his customers nor claim any credit of tax paid by him.
Entities with turnover exceeds of Rs.40 lakhs (supply of goods in normal state), Rs.20 lakhs (supply of goods/services in normal state), Rs.20 lakhs (supply of goods in specific state) or Rs. 10 Lakhs (Supply of goods/services specific state) and above would be required to register under GST.
The eligible entities must file GST application within 30 days from the date on which the entity became liable for registration under GST law.