Polyester polyols, processes for making them, and applications for the polyols are disclosed. In some aspects, the polyols comprise recurring units from a thermoplastic polyester or an aromatic polyacid source, a glycol, and a lignin, tannin, or mixture thereof. Optionally, the polyols incorporate recurring units of a hydrophobe. The polyols are made in one or multiple steps; in some aspects, the thermoplastic polyester or aromatic polyacid source and the glycol are reacted first, followed by reaction with the lignin, tannin, or mixture thereof. High-recycle-content polyols having desirable properties and attributes for formulating polyurethane products, including two-component polyurethane coatings, can be made. The polyols provide a sustainable alternative to bio- or petrochemical-based polyols.