v3.25.3

Document and Entity Information	Oct. 21, 2025
Document Type	8-K
Document Period End Date	Oct. 21, 2025
Entity Registrant Name	Chubb Limited
Entity Incorporation State Country Code	V8
Entity File Number	1-11778
Entity Tax Identification Number	98-0091805
Entity Address Address Line 1	Baerengasse 32
Entity Address Postal Zip Code	8001
Entity Address City Or Town	Zurich
Entity Address Country	CH
Country Region	41
City Area Code	(0)43
Local Phone Number	456 76 00
Written Communications	false
Soliciting Material	false
Pre Commencement Tender Offer	false
Pre Commencement Issuer Tender Offer	false
Entity Emerging Growth Company	false
Amendment Flag	false
Entity Central Index Key	0000896159
Common Class A [Member]
Security 12b Title	Common Shares, par value CHF 0.50 per share
Trading Symbol	CB
Security Exchange Name	NYSE
Guarantee of Chubb INA Holdings LLC 0.875% Senior Notes due 2027 [Member]
Security 12b Title	Guarantee of Chubb INA Holdings LLC 0.875% Senior Notes due 2027
Trading Symbol	CB/27
Security Exchange Name	NYSE
Guarantee of Chubb INA Holdings LLC 1.55% Senior Notes due 2028 [Member]
Security 12b Title	Guarantee of Chubb INA Holdings LLC 1.55% Senior Notes due 2028
Trading Symbol	CB/28
Security Exchange Name	NYSE
Guarantee of Chubb INA Holdings LLC 0.875% Senior Notes due 2029 [Member]
Security 12b Title	Guarantee of Chubb INA Holdings LLC 0.875% Senior Notes due 2029
Trading Symbol	CB/29A
Security Exchange Name	NYSE
Guarantee of Chubb INA Holdings LLC 1.40% Senior Notes due 2031 [Member]
Security 12b Title	Guarantee of Chubb INA Holdings LLC 1.40% Senior Notes due 2031
Trading Symbol	CB/31
Security Exchange Name	NYSE
Guarantee of Chubb INA Holdings LLC 2.50% Senior Notes due 2038 [Member]
Security 12b Title	Guarantee of Chubb INA Holdings LLC 2.50% Senior Notes due 2038
Trading Symbol	CB/38A
Security Exchange Name	NYSE

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Area code of city

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

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Address Line 1 such as Attn, Building Name, Street Name

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Name of the City or Town

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ISO 3166-1 alpha-2 country code.

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A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Indicate if registrant meets the emerging growth company criteria.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

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Two-character EDGAR code representing the state or country of incorporation.

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The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Local phone number for entity.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Title of a 12(b) registered security.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Name of the Exchange on which a security is registered.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Exchange Act
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-Subsection 12

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Trading symbol of an instrument as listed on an exchange.

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No definition available.

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Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Securities Act
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Chubb Ltd 8-K