Series IV. Phillips Family Businesses, 1849-1888, is divided into the lumbering papers, the forwarding merchant and railroad shipping papers, and the papers of other family enterprises.

Subseries A. Lumbering Papers, 1854-1860, documents the day-to-day running of the family's timber concern in Canada, the financial problems of the company and its sale circa 1860. The papers are primarily comprised of correspondence among George William Phillips, the overseer of operations at Three Rivers Quebec, Willard P. Phillips, the company treasurer, and Stephen C. Phillips. Also included is correspondence with Nicholas G. Norcross of Lowell, one of the firm's partners.

Subseries B. Forwarding Merchant and Railroad Shipping Papers documents business conducted at Phillips Wharf from 1849 to 1888. These papers reflect the quantities of coal, grain, flour, lumber, sugar, plaster, cement, and other commodities which were shipped over the Salem and Lowell Railroad and other railway lines. Included is correspondence from the last year of business (1854) of Phillips, Goodhue, and Bowker, a forwarding merchant firm in which both Stephen C. and Willard P. Phillips were involved. The station agents' correspondence, primarily of the Salem agent Edward H. Knight, and Phillips Wharf accounts reflect the uninterrupted flow of trade at the Wharf. Included in the printed material are annual reports of the Illinois Central, Salem and Lowell, Lowell and Lawrence, and Northern Railroads.

Subseries C. Other Phillips Enterprises includes receipts, reports, and a prospectus relating to the Ice Company at Haggett's Pond, the Salem Ice Company, the Argillite and Greenup Coal and Iron Company, and other concerns in which the Phillips' were interested.