Celsion Employee Benefit Plans	12 Months Ended
Dec. 31, 2019
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, 2019 and 2018 was $105,999 and $93,948 respectively. During 2018, the Company also provided a discretionary contribution totaling $181,999 which represented 6% of each eligible participant’s annual salary in each of 2018. This amount was paid in January 2019.

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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