Salary Structure Changed After 5 Months Of Joining.

Hi,
I have joined an IT company with signing the offer-cum-appointment letter with written monthly salary structure.
But after 5 months, HR has suddenly changed my salary structure including HRA and BASIC without any prior notification and my acceptance.
Does HR has any such power to do alteration in salary structure of any employee?
If YES, then shouldn't it necessary to mention this in the appointment/offer letter which was handed over to me at the time of joining?
If NO, the what should an employee can do?
Thanks.

Industrial Disputes Act prohibits any change of service condition of employee without notice and mutual agreement. This Act will be applicable to you if you fall within the category of 'workman'.
HR has to abide by the law of the land and cannot act arbitrarily.
You can initially raise the dispute before the management by sending a protest letter. Make sure you have a proper acknowledgment of the said letter for future reference, if required.

Salary structures, specially basic is not changed unless there is a strategic reason and the employees are taken into approval. So, you need to ask your HR why it was changed.
But equally important is whether the change has any adverse impact on you, both short and long term.

Ms Banerjee and others have amply clarified rule position.
You need to check the affect of change , both long short term and long term before taking action.Also seek clarification from HR as what will be effect on PF contribution, on gratuity etc AND reason for the change.
Best Wishes,
Col.Rathi

HAPPY NEW YEAR 2017 TO ALL CITE HR MEMBERS, TEAM LEADERS.
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Reg. HR changing salary structure-
Sometimes, HR will change, modify the allowances due to changes in PF,ESI, IT Acts etc., to protect the interest of Co. & Also the employees concerned. HR also mentions in Apptt.Orders that the Management may change, merge Basic, HRA etc., to take care of such changes in any Act; but will inform employees before doing it - to avoid unpleasantness later;
So; as informed by Seniors, pl. contact HR for the changes; if it has resulted in any loss to the employee.
[Login to view] 1.1.2017

It is only mentioned that structure had been changed. If your gross or CTC AND basic salary is maintained you need not worry. Also if your tax liability should not be increased.
Yes, under section 9A of the ID Act 21 days' prior notice should have been given. But if the above points are true in your case, don't bother about these legalities too much.b