Subsequent Events	12 Months Ended
Dec. 31, 2024
Subsequent Events [Abstract]
Subsequent Events	20. Subsequent Events Amendment to Amended Note Purchase Agreement, RIFA Amendment, and New RIFA On January 7, 2025, the Company and Allurion Technologies, LLC ("Allurion OpCo") entered into an Omnibus Amendment (the “Omnibus Amendment”) with Allurion Australia Pty Ltd, Allurion France, and RTW to amend the Amended Note Purchase Agreement, the RIFA Amendment, and the New RIFA. The Omnibus Amendment requires, among other things, (i) the Company and Allurion OpCo to maintain certain minimum balances of unrestricted cash in controlled accounts in the U.S. in the amounts corresponding to the calculations set forth therein, and (ii) the Company to receive minimum trailing twelve-month consolidated Revenue (as defined in the Amended Note Purchase Agreement) in amounts set forth therein, tested quarterly beginning with the twelve-month period ending September 30, 2025. The Omnibus Amendment also requires that (i) Allurion France shall have successfully regained marketing authorization from ANSM in France on or prior to December 31, 2025 and (ii) Allurion OpCo shall have received Marketing Authorization from the U.S. Food & Drug Administration for the Commercialization of the Product in the United States no later than June 30, 2026. Pursuant to the Omnibus Amendment, the Investors and the Purchasers will receive a number of shares of the Company’s Common Stock, representing in the aggregate five percent (5%) of the fully-diluted shares outstanding immediately after the closing of the offering and sale of Additional Shares (as defined in the Existing Documents) to be consummated no later than February 15, 2025, in connection with which the Company shall have raised at least $12,000,000 aggregate net proceeds (the “Amendment Fee”); provided that, in the event the Company cannot issue shares of Common Stock to the investors and the purchasers due to applicable law or NYSE listing rules, the Company will instead issue an equivalent (as-converted) number of shares of a newly created series of Series A-1 non-voting preferred stock (the “Series A-1 Preferred Stock”) and the Company shall include a proposal in a definitive proxy statement on Schedule 14A seeking stockholder approval no later than December 31, 2025 to allow the conversion of Series A-1 Preferred Stock into Common Stock; provided further that, each share of Series A-1 Preferred Stock outstanding on December 31, 2026 will, except to the extent prohibited by Delaware law governing distributions to stockholders (including the Delaware General Corporation Law), be redeemed by the Company for cash in an amount equal to the as-converted value of the underlying common stock. RTW Private Placement On January 14, 2025, Allurion Technologies, Inc. (the “Company”) entered into a subscription agreement (the “Subscription Agreement”) with funds affiliated with RTW, pursuant to which the Company agreed to sell to RTW 841,751 shares of its common stock, par value $0.0001 per share, for an aggregate purchase price of approximately $2.5 million at a purchase price per share of $2.97 (the “RTW Private Placement”). The Private Placement closed on January 16, 2025. January 2025 Public Offering and Concurrent Private Placement On January 24, 2025, the Company entered into a securities purchase agreement (the “January 2025 Securities Purchase Agreement”) with certain accredited investors named therein, pursuant to which the Company agreed to issue and sell 1,240,000 shares of the Company’s Common Stock (the “January 2025 Offering”) and 1,240,000 accompanying common warrants (the “January 2025 Warrants”) to purchase up to 1,240,000 shares of Common Stock upon exercise of the January 2025 Common Warrants in a concurrent private placement (the “January 2025 Private Placement”), at an offering price of $6.00 per share and accompanying January 2025 Common Warrant. The January 2025 Offering and January 2025 Private Placement resulted in gross proceeds to the Company of approximately $7.4 million, before deducting the placement agent fees and commissions and estimated offering expenses payable by the Company. The January 2025 Offering and January 2025 Private Placement closed on January 27, 2025. The Company intends to use the net proceeds of the January 2025 Offering and January 2025 Private Placement for working capital and other general corporate purposes. Certain purchasers in the January 2025 Offering and January 2025 Private Placement are holders of warrants to purchase Common Stock issued in the Public Offering in July 2024. The exercise price for the Public Offering Warrants initially was $30.00 per share. In consideration for such purchasers’ purchase of securities in the January 2025 Offering and January 2025 Private Placement, we have agreed with each such purchaser to seek stockholder approval to reduce the exercise price of the Public Offering Warrants held by such purchasers to $6.00 per share. Such Public Offering Warrants will become exercisable at the revised exercise price upon the receipt of such stockholder approval. February 2025 Public Offering and Concurrent Private Placement On February 19, 2025, the Company entered into a securities purchase agreement (the “February 2025 Securities Purchase Agreement”) with certain accredited investors named therein, pursuant to which the Company agreed to issue and sell 900,000 shares of the Company’s Common Stock (the “February 2025 Offering”), and 1,800,000 accompanying common warrants (the “February 2025 Warrants”) to purchase up to 1,800,000 shares of Common Stock upon exercise of the February 2025 Common Warrants in a concurrent private placement (the “February 2025 Private Placement”), at an offering price of $5.23 per share and accompanying Common Warrant. The February 2025 Offering and February 2025 Private Placement resulted in gross proceeds to the Company of approximately $4.7 million, before deducting the placement agent fees and commissions and estimated offering expenses payable by the Company. The February 2025 Offering and February 2025 Private Placement closed on February 20, 2025. The Company intends to use the net proceeds of the February 2025 Offering and February 2025 Private Placement to fund its clinical pipeline testing the effects of the combination of the Allurion Balloon and GLP-1 therapy on muscle mass and long-term GLP-1 adherence, for working capital and other general corporate purposes. Leavitt Private Placement On February 19, 2025, the Company entered into a subscription agreement (the “Leavitt Subscription Agreement”) with an accredited investor affiliated with Leavitt Equity Partners LLC (collectively, “Leavitt”), pursuant to which the Company agreed to sell to Leavitt 267,686 shares of Common Stock (the “Private Placement Shares”) and common warrants to purchase up to 535,372 shares of Common Stock (the “Leavitt Private Placement Warrants” and together with the Private Placement Shares, the “Private Placement Securities”), for an aggregate purchase price of approximately $1.4 million at a purchase price of $5.23 per share and accompanying Private Placement Warrant (the “Leavitt Private Placement”). The Leavitt Private Placement closed on February 20, 2025.

Subsequent Events

12 Months Ended

Dec. 31, 2024

20. Subsequent Events

Amendment to Amended Note Purchase Agreement, RIFA Amendment, and New RIFA

On January 7, 2025, the Company and Allurion Technologies, LLC ("Allurion OpCo") entered into an Omnibus Amendment (the “Omnibus Amendment”) with Allurion Australia Pty Ltd, Allurion France, and RTW to amend the Amended Note Purchase Agreement, the RIFA Amendment, and the New RIFA.

The Omnibus Amendment requires, among other things, (i) the Company and Allurion OpCo to maintain certain minimum balances of unrestricted cash in controlled accounts in the U.S. in the amounts corresponding to the calculations set forth therein, and (ii) the Company to receive minimum trailing twelve-month consolidated Revenue (as defined in the Amended Note Purchase Agreement) in amounts set forth therein, tested quarterly beginning with the twelve-month period ending September 30, 2025. The Omnibus Amendment also requires that (i) Allurion France shall have successfully regained marketing authorization from ANSM in France on or prior to December 31, 2025 and (ii) Allurion OpCo shall have received Marketing Authorization from the U.S. Food & Drug Administration for the Commercialization of the Product in the United States no later than June 30, 2026.

Pursuant to the Omnibus Amendment, the Investors and the Purchasers will receive a number of shares of the Company’s Common Stock, representing in the aggregate five percent (5%) of the fully-diluted shares outstanding immediately after the closing of the offering and sale of Additional Shares (as defined in the Existing Documents) to be consummated no later than February 15, 2025, in connection with which the Company shall have raised at least $12,000,000 aggregate net proceeds (the “Amendment Fee”); provided that, in the event the Company cannot issue shares of Common Stock to the investors and the purchasers due to applicable law or NYSE listing rules, the Company will instead issue an equivalent (as-converted) number of shares of a newly created series of Series A-1 non-voting preferred stock (the “Series A-1 Preferred Stock”) and the Company shall include a proposal in a definitive proxy statement on Schedule 14A seeking stockholder approval no later than December 31, 2025 to allow the conversion of Series A-1 Preferred Stock into Common Stock; provided further that, each share of Series A-1 Preferred Stock outstanding on December 31, 2026 will, except to the extent prohibited by Delaware law governing distributions to stockholders (including the Delaware General Corporation Law), be redeemed by the Company for cash in an amount equal to the as-converted value of the underlying common stock.

RTW Private Placement

On January 14, 2025, Allurion Technologies, Inc. (the “Company”) entered into a subscription agreement (the “Subscription Agreement”) with funds affiliated with RTW, pursuant to which the Company agreed to sell to RTW 841,751 shares of its common stock, par value $0.0001 per share, for an aggregate purchase price of approximately $2.5 million at a purchase price per share of $2.97 (the “RTW Private Placement”). The Private Placement closed on January 16, 2025.

January 2025 Public Offering and Concurrent Private Placement

On January 24, 2025, the Company entered into a securities purchase agreement (the “January 2025 Securities Purchase Agreement”) with certain accredited investors named therein, pursuant to which the Company agreed to issue and sell 1,240,000 shares of the Company’s Common Stock (the “January 2025 Offering”) and 1,240,000 accompanying common warrants (the “January 2025 Warrants”) to purchase up to 1,240,000 shares of Common Stock upon exercise of the January 2025 Common Warrants in a concurrent private placement (the “January 2025 Private Placement”), at an offering price of $6.00 per share and accompanying January 2025 Common Warrant.

The January 2025 Offering and January 2025 Private Placement resulted in gross proceeds to the Company of approximately $7.4 million, before deducting the placement agent fees and commissions and estimated offering expenses payable by the Company. The January 2025 Offering and January 2025 Private Placement closed on January 27, 2025. The Company intends to use the net proceeds of the January 2025 Offering and January 2025 Private Placement for working capital and other general corporate purposes.

Certain purchasers in the January 2025 Offering and January 2025 Private Placement are holders of warrants to purchase Common Stock issued in the Public Offering in July 2024. The exercise price for the Public Offering Warrants initially was $30.00 per share. In consideration for such purchasers’ purchase of securities in the January 2025 Offering and January 2025 Private Placement, we have agreed with each such purchaser to seek stockholder approval to reduce the exercise price of the Public Offering Warrants held by such purchasers to $6.00 per share. Such Public Offering Warrants will become exercisable at the revised exercise price upon the receipt of such stockholder approval.

February 2025 Public Offering and Concurrent Private Placement

On February 19, 2025, the Company entered into a securities purchase agreement (the “February 2025 Securities Purchase Agreement”) with certain accredited investors named therein, pursuant to which the Company agreed to issue and sell 900,000 shares of the Company’s Common Stock (the “February 2025 Offering”), and 1,800,000 accompanying common warrants (the “February 2025 Warrants”) to purchase up to 1,800,000 shares of Common Stock upon exercise of the February 2025 Common Warrants in a concurrent private placement (the “February 2025 Private Placement”), at an offering price of $5.23 per share and accompanying Common Warrant.

The February 2025 Offering and February 2025 Private Placement resulted in gross proceeds to the Company of approximately $4.7 million, before deducting the placement agent fees and commissions and estimated offering expenses payable by the Company. The February 2025 Offering and February 2025 Private Placement closed on February 20, 2025. The Company intends to use the net proceeds of the February 2025 Offering and February 2025 Private Placement to fund its clinical pipeline testing the effects of the combination of the Allurion Balloon and GLP-1 therapy on muscle mass and long-term GLP-1 adherence, for working capital and other general corporate purposes.

Leavitt Private Placement

On February 19, 2025, the Company entered into a subscription agreement (the “Leavitt Subscription Agreement”) with an accredited investor affiliated with Leavitt Equity Partners LLC (collectively, “Leavitt”), pursuant to which the Company agreed to sell to Leavitt 267,686 shares of Common Stock (the “Private Placement Shares”) and common warrants to purchase up to 535,372 shares of Common Stock (the “Leavitt Private Placement Warrants” and together with the Private Placement Shares, the “Private Placement Securities”), for an aggregate purchase price of approximately $1.4 million at a purchase price of $5.23 per share and accompanying Private Placement Warrant (the “Leavitt Private Placement”). The Leavitt Private Placement closed on February 20, 2025.