> What is a relieving letter?

In India there are various restrictions (both in law and as part of employment contracts) which prevent a person to have more than one job at a time (see for example [Dual Employment Rules in India](https://www.myadvo.in/blog/dual-employment-rules-in-india/) and [Can you legally work at two different companies in India?](https://blog.ipleaders.in/legal-working-in-two-companies-india-moonlighting-clause/)). A relieving letter is issued by a company to an employee who has duly resigned from his said post, to be used as proof for future employers.

> When do you get a relieving letter?

The relieving letter should be issued the same day you are going to leave the company. If the company does not issue the relieving letter it means that your resignation is not accepted and you are still an employee of that company until the company issues the relieving letter.
 
> What are they used for?

Relieving letter only states formally that you have been relieved to ensure that a new employee has resigned from his previous company and he is not trying to work two jobs at the same time.  This prevents people from taking a holiday to try out another company.

It will function as a notification to the employee, that his/her resignation has been accepted and he is relieved from his current duties.

Format of relieving letter

    TO WHOM - SO - EVER IT MAY CONCERN
    
    THIS IS TO CERTIFY THAT MR. ..................... HAS WORKED WITH US
    AS................................. FROM .......................  
    TO .......................... SUBSEQUENT TO HIS RESIGNATION 
    DT................... , HE HAS BEEN RELEIVED FROM HIS DUTIES 
    W.E.F...............
    
    
    (AUTHORIZED SIGNATORY)
    
    
    Thanks

The above is a sample format of relieving letter, it may vary from company to company.

> Do you need to keep all of them or just the most recent letter?

Most of companies are interested only in your most recent position, but some [CMM][1] level 5 companies require all of your relieving, experience, payslips for verification.
Companies like Infosys, TCS, CTS verify all the documents and also verify your educational qualification which includes your schooling and degree.

Background check practices in India vary significantly across different sectors, and even across different companies within the same sector, without defined principles, processes or laws. A comprehensive background check requires a prospective employer to validate a candidate’s educational qualifications, past employment records, work experience, criminal records and identity check, such as passport, driving license or income tax registration number. An effective validation process also may involve contacting past employers, former managers and supervisors.

> What are the consequences of not receiving a relieving letter when you
> leave an employer?

Most organization would at-most do one level of verification which is the latest, most recent relieving letter.

If you don't have the most recent relieving letter, there are greater chances of job application **being dropped**, regardless if you are a potential candidate or not. The employer has no way to know whether or not you have been relieved from your last assignment and that there are no pending engagements with your last employer.

Weeding out candidates with fudged resumes and preventing fraud requires a vigilant eye and a reliable method for background screening. 

Indian companies have started realizing that an effective due diligence process for candidates can help reduce workplace-related problems such as theft, embezzlement, violence, injury and harassment. Such practices can also help mitigate the risks of potential lawsuits as a result of negligent hiring.


  [1]: http://en.wikipedia.org/wiki/Capability_Maturity_Model