Nyassa refers to a short-lived but visually striking postal entity in southeastern Africa, corresponding to part of present-day northern Mozambique. Issued between 1898 and 1929, Nyassa stamps were produced under the authority of the Companhia do Nyassa, a Portuguese chartered company granted administrative control over the region.

Nyassa issues are especially admired for their ornate engraving, rich color palettes, and evocative imagery, frequently depicting African wildlife, sailing ships, allegorical figures, and Portuguese heraldic elements. Many designs reflect the aesthetics of late-19th- and early-20th-century colonial stamp production, with dramatic vignettes and finely detailed frames.

Although Nyassa stamps were valid for postal use during their period, much of their appeal today lies in their philatelic artistry and historical context rather than heavy postal usage. Surviving examples range from genuinely postally used issues to stamps created primarily for collectors, making condition and cancellation an important consideration for specialists.

This category includes definitive and commemorative issues, with a variety of denominations, colors, and design types. Nyassa remains a popular collecting area for those interested in Portuguese colonial history, African regional issues, and classic engraved stamps, offering strong visual impact and a fascinating glimpse into a brief colonial chapter of postal history.