People
often change their jobs for various reasons. If you have switched your job in the middle of the financial year, you will have to provide details of your previous salary earned along with tax deductions to the new employer through Form 12B. When you submit your Form 12B, your the current employer can deduct the correct amount of TDS or Tax Deducted at
Source from your salary. Every new employee has to submit Form 12B to
their new employer along with proofs of all the investments made before
31st March.