Business overview and basis of presentation	9 Months Ended
Jun. 30, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business overview and basis of presentation	Business overview and basis of presentation Description of business Sonos, Inc. (collectively with its wholly owned subsidiaries, “Sonos,” the “Company,” “we,” “us,” or “our”) designs, develops, manufactures and sells multi-room audio products primarily for use in private residences. The Sonos home sound system provides customers with an immersive listening experience created by the design of its speakers and components, a proprietary software platform and the ability to stream content from a variety of sources throughout the home over the customer’s wireless network. The Company’s products are sold through third-party retail stores, including custom installers of home audio systems. The Company also sells through select e-commerce retailers and its website sonos.com. The Company’s products are distributed in over 50 countries through its wholly owned subsidiaries: Sonos Europe B.V., Beijing Sonos Technology Co., Ltd. and Sonos Australia Pty Ltd., located in the Netherlands, China and Australia, respectively. Initial public offering On August 6, 2018, the Company completed its initial public offering (the "IPO") of its common stock, in which it sold 6,388,888 shares of its common stock, including 833,333 shares of its common stock pursuant to the underwriters’ over-allotment option, and selling stockholders sold 9,583,333 shares of the Company's common stock, including 1,250,000 shares pursuant to the underwriters' over-allotment option. The shares were sold at the IPO price of $15.00 per share for net proceeds of $90.6 million, after deducting underwriting discounts and commissions of $5.3 million. Additionally, offering costs incurred by the Company are expected to total approximately $4.6 million. Upon the closing of the IPO, all outstanding shares of the Company's redeemable convertible preferred stock automatically converted into 32,482,590 shares of common stock on a one-for-one basis. Basis of presentation and preparation The accompanying condensed consolidated financial statements are unaudited. The condensed consolidated balance sheet as of September 30, 2017 has been derived from the audited financial statements of the Company. The accompanying condensed financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”) for interim financial information, and in management’s opinion, includes all adjustments, consisting of only normal recurring adjustments, necessary for the fair statement of the Company’s financial position, its results of operations and cash flows for the interim periods presented. The results of operations for the three and nine months ended June 30, 2018 are not necessarily indicative of the results to be expected for the full fiscal year or any other period. The accompanying condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto contained in the Company’s prospectus filed pursuant to Rule 424(b) under the Securities Act of 1933, as amended (the "Securities Act"), with the Securities and Exchange Commission (“SEC”) on August 2, 2018 (the "Final Prospectus"). The Company has a 4-4-5 fiscal year ending on the Saturday nearest September 30 each year. The Company’s fiscal year is divided into four quarters of 13 weeks, each beginning on a Sunday and containing two 4-week months followed by a 5-week “month.” An additional week is included in the fourth fiscal quarter approximately every five years to realign fiscal quarters with calendar quarters. This last occurred in the fourth quarter of the Company’s fiscal year ended October 3, 2015. The nine months ended June 30, 2018 and July 1, 2017 spanned 39 weeks each. Stock split On July 19, 2018, the Company effected a two-for-one stock split of all outstanding shares of the Company’s capital stock, including its common stock and its redeemable convertible preferred stock. All share and per share information presented in the condensed consolidated financial statements has been retroactively adjusted for all periods presented for the effects of the stock split. Use of estimates and judgments The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and judgments that affect the amounts reported and disclosed in the condensed consolidated financial statements and accompanying notes. Actual results could differ materially from those estimates. On an ongoing basis, the Company evaluates its estimates and judgments compared to historical experience and expected trends.

Business overview and basis of presentation

Description of business

Sonos, Inc. (collectively with its wholly owned subsidiaries, “Sonos,” the “Company,” “we,” “us,” or “our”) designs, develops, manufactures and sells multi-room audio products primarily for use in private residences. The Sonos home sound system provides customers with an immersive listening experience created by the design of its speakers and components, a proprietary software platform and the ability to stream content from a variety of sources throughout the home over the customer’s wireless network.

The Company’s products are sold through third-party retail stores, including custom installers of home audio systems. The Company also sells through select e-commerce retailers and its website sonos.com. The Company’s products are distributed in over 50 countries through its wholly owned subsidiaries: Sonos Europe B.V., Beijing Sonos Technology Co., Ltd. and Sonos Australia Pty Ltd., located in the Netherlands, China and Australia, respectively.

Initial public offering

On August 6, 2018, the Company completed its initial public offering (the "IPO") of its common stock, in which it sold 6,388,888 shares of its common stock, including 833,333 shares of its common stock pursuant to the underwriters’ over-allotment option, and selling stockholders sold 9,583,333 shares of the Company's common stock, including 1,250,000 shares pursuant to the underwriters' over-allotment option. The shares were sold at the IPO price of $15.00 per share for net proceeds of $90.6 million, after deducting underwriting discounts and commissions of $5.3 million. Additionally, offering costs incurred by the Company are expected to total approximately $4.6 million. Upon the closing of the IPO, all outstanding shares of the Company's redeemable convertible preferred stock automatically converted into 32,482,590 shares of common stock on a one-for-one basis.

Basis of presentation and preparation

The accompanying condensed consolidated financial statements are unaudited. The condensed consolidated balance sheet as of September 30, 2017 has been derived from the audited financial statements of the Company. The accompanying condensed financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”) for interim financial information, and in management’s opinion, includes all adjustments, consisting of only normal recurring adjustments, necessary for the fair statement of the Company’s financial position, its results of operations and cash flows for the interim periods presented. The results of operations for the three and nine months ended June 30, 2018 are not necessarily indicative of the results to be expected for the full fiscal year or any other period.

The accompanying condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto contained in the Company’s prospectus filed pursuant to Rule 424(b) under the Securities Act of 1933, as amended (the "Securities Act"), with the Securities and Exchange Commission (“SEC”) on August 2, 2018 (the "Final Prospectus").

The Company has a 4-4-5 fiscal year ending on the Saturday nearest September 30 each year. The Company’s fiscal year is divided into four quarters of 13 weeks, each beginning on a Sunday and containing two 4-week months followed by a 5-week “month.” An additional week is included in the fourth fiscal quarter approximately every five years to realign fiscal quarters with calendar quarters. This last occurred in the fourth quarter of the Company’s fiscal year ended October 3, 2015. The nine months ended June 30, 2018 and July 1, 2017 spanned 39 weeks each.

Stock split

On July 19, 2018, the Company effected a two-for-one stock split of all outstanding shares of the Company’s capital stock, including its common stock and its redeemable convertible preferred stock. All share and per share information presented in the condensed consolidated financial statements has been retroactively adjusted for all periods presented for the effects of the stock split.

Use of estimates and judgments

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and judgments that affect the amounts reported and disclosed in the condensed consolidated financial statements and accompanying notes. Actual results could differ materially from those estimates. On an ongoing basis, the Company evaluates its estimates and judgments compared to historical experience and expected trends.