Benefit Plans	12 Months Ended
Dec. 31, 2025
Benefit Plans
Benefit Plans	18. Benefit Plans The Company has established a defined-contribution savings plan under Section 401(k) of the Internal Revenue Code. This plan covers substantially all Kiniksa US employees who meet minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis. The Company provides matching contributions of 100% of the first 3% of each participant’s salary contributed, plus 50% for each of the next 2% contributed. Employees are immediately and fully vested in their own contributions and the Company’s match. During the years ended December 31, 2025, 2024 and 2023, the Company contributed $3,544, $2,923 and $2,305 respectively, to the plan.

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 715
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/715/tableOfContent

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 712
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/712/tableOfContent

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 710
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/710/tableOfContent

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 718
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/718/tableOfContent

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