At Ask Me Help Desk you can ask questions in any topic and have them
answered for free by our experts. To ask questions or participate in
answering them you must register for a free account. By registering you
will be able to:
Get free answers from experts in any of our 300+
topics.
The employer is required to send it before January 31st so you should wait.
Normally you can get Employer's ID from old W2, but it is always better to wait for current W2. If the employer has major restructure of partners or shareholder or change of proprietorship, then there can be a different ID.
You can always do the basework using your last pay stub info, but wait for filing.