Celsion Employee Benefit Plans	12 Months Ended
Dec. 31, 2020
Postemployment Benefits [Abstract]
Celsion Employee Benefit Plans	14. CELSION EMPLOYEE BENEFIT PLANS Celsion maintains a defined-contribution plan under Section 401(k) of the Internal Revenue Code. The plan covers substantially all employees over the age of 21. Participating employees may defer a portion of their pretax earnings, up to the IRS annual contribution limit. The Company makes a matching contribution up to a maximum of 3% of an employee’s annual salary. The Company’s total matching contributions for the years ended December 31, 2020 and 2019 was $111,000 and $106,000, respectively. During 2020, the Company also provided a discretionary contribution totaling $178,000 which represented 6% of each eligible participant’s annual salary in 2020. This amount was paid in January 2021.

The entire disclosure for an entity's employee compensation and benefit plans, including, but not limited to, postemployment and postretirement benefit plans, defined benefit pension plans, defined contribution plans, non-qualified and supplemental benefit plans, deferred compensation, share-based compensation, life insurance, severance, health care, unemployment and other benefit plans.

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