UPSC has started a new type of registration which is called OTR. In OTR you have to register only for one with basic details. In One Time Registration, You have to fill in your basic details like personal details. All the data should match with the 10th class mark sheet data.
Basically, It was started by UPSC for the convenience of Aspirants. Every time when UPSC released a notification for the application form of particular, You have to fill in your details again and again. To remove this hurdle UPSC came with one-time registration. It is like SSC Registration and Login system.
Is OTR compulsory for UPSC?
Yes, if you want to apply for the exams conducted by UPSC then it is compulsory. Without OTR you can not apply directly for Government jobs.
When you will register for OTR on UPSC then you will get some login credentials like an id password to access your account on UPSC.
When UPSC releases any kind of Notification for Government jobs then you have to log in with your id password. After logging in you will see the notification and apply button for particular government jobs.
Now, you can apply for that job by clicking on apply now, before OTR or One-time registration you have to fill in all details but now you have already provided some personal details in the OTR. So just fill up some more details regarding notification, you have to fill in some more details according to the notification. It may vary from one notification to another notification like you have to fill in some different details for UPSC CSE and some different details for UPSC IES /ISS. Application details depend on government job eligibility criteria.
This is necessary and compulsory for any UPSC aspirant.
How to fill up one-time registration in UPSC?
This is the basic question. Everyone wants to know the correct method to fill up a one-time registration for UPSC. So do not worry I am going to tell you about “How To Register for UPSC One Time Registration”
Here is the step-by-step tutorial on how to register for UPSC OTR
05 5 minutes
Go to the Offical website
From Here you can go to the UPSC OTR website. After reaching the official website you will see two tabs
One is already registered and the Second is New Registration. You can see this in The image below.
I Hope You can see both of these tabs highlighted in Red color in a rectangle shape.
Registration
Firstly, you must have the 10th mark sheet, Aadhaar Card, and Mobile Number with you.
Now Click on “Registration ” or Go direct from here.
Applicant Must submit these details –
Name and Verify the name
Full Name If Any
Gender and Verify Gender
Date of birth and verify date of birth
Father’s name and verify the father’s name.
Mother’s name and verify mother’s name
Minority status
Valid mobile number ( To be used as login id )
Alternate mobile number if any
Valid Email Id to be used as Login id
Alternate email id if any
Board examination number class 10th
Security Questions
Check the Image of the Registration form
After submission of the correct details click on submit and you will OTP fill up that OTP and Click on Verify.
Now you will get all the messages related to UPSC OTR, you will get the OTR id on SMS.
You can set your password also in this process. 
Login
Now you have login with your credentials like mobile number or Email id or by OTR ID and password. you can choose which suits you most.
Do log in now, go official website, or do it from here.
Now you have Successfully Registered for UPSC One Time Registration. 
UPSC OTR Registration last date
UPSC has not defined any last date for UPSC one-time registration. Time Registration does not have any last date, it will be open throughout the year. You can register for this when you want to be an Aspirant of UPSC.
If you have any doubt regarding this then let me know in the comment section I eagerly help you.