Am I considered covered by a retirement plan at work if I'm not covered part of the year, including tax year end?

Yes.

The IRS considers you covered by an employer's plan if you were covered at any time during the tax year.

According to the IRS:

"You’re covered by an employer retirement plan for a tax year if your employer (or your spouse’s employer) has a:

• Defined contribution plan (profit-sharing, 401(k), stock bonus and money purchase pension plan) and any contributions or forfeitures were allocated to your account for the plan year ending with or within the tax year;
• IRA-based plan (SEP, SARSEP or SIMPLE IRA plan) and you had an amount contributed to your IRA for the plan year that ends with or within the tax year; or
• Defined benefit plan (pension plan that pays a retirement benefit spelled out in the plan) and you are eligible to participate for the plan year ending with or within the tax year."

CLICK HERE for IRS retirement plan coverage information

Am I still considered covered by a retirement plan through my employer if my employer contributes to a SEP but I have not made a contributions to the SEP from my payroll?

Yes.  Also the retirement plan box should be checked on your W2 in box 13.

What if box 13 is checked and I did not contribute nor my employer. Can I still deduct an IRA contribution?

According to the IRS you may not be able to deduct all of your traditional IRA contributions if you or your spouse participates in another retirement plan at work (please see IRS Retirement Topics - IRA Contribution Limits for details). Therefore, if you did not participate all year then you will be able to deduct all of your traditional IRA contribution.

If neither you nor your employer contributed to the 401k then you might want to ask why the retirement plan in box 13 is checked.

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