Segmentation by membrane type classifies the market into microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), reverse osmosis (RO), and emerging forward osmosis (FO). MF and UF together capture roughly 55 % of sales, with MF targeting particles > 0.1 µm for pretreatment and UF retaining macromolecules up to 0.01 µm in dairy, biotech, and water reuse. NF, accounting for about 20 % of the market, bridges the gap between UF and RO, enabling selective removal of divalent ions and organic contaminants in softening and concentrate reduction applications. RO dominates the high‑pressure segment with a 25 % share, driven by desalination, high‑purity water, and pharmaceutical manufacturing where near‑total solute rejection is mandatory. Forward osmosis, still nascent, holds less than 5 % but is gaining traction for low‑energy concentration processes in food processing and wastewater reuse. This type‑based taxonomy clarifies how performance specifications, operating pressure, and material costs allocate revenue across the Membrane for Filtration market.