Accepted a postdoc offer by just emailing, have not signed any contract, what to do if other offer comes Hi I am a Phd student (Phd thesis submitted). Recently, I have received a postdoc offer from a reputed university and accordingly accepted the offer by emailing them. Now this is just a offer letter, no salary is written there (the PI has told me unofficially the salary amount). In order to join the job, I have to defend my Phd thesis, then they will send a formal joining letter (where salary will be written). In other words, I have not signed any contract till now. Now, my Phd thesis reviews have not come yet (in my country thesis is sent to two reviewers: one within and one outside the country). Till I defend my Phd thesis what should I do if I get postdoc offer from other places. 

Any help/suggestions will be useful. Thanks in advance.
Your honor is at stake here. The email should constitute an agreement, even if not legally binding yet. You can, of course, by mutual agreement with the PI, still change your acceptance, indicating that it is tentative because of the restriction. This should be easy and natural, if the condition was raised after your "acceptance." 

Just don't get yourself in the position of the PI thinking he has "caught" you and you later "get away." The consequences will be on you.