No, Uzwil Railway Station (ZKX) does not have a lounge, and it never will, because it is not an airport at all: it is a Swiss Federal Railways stop in the town of Uzwil, canton St. Gallen, carrying an airport-style code purely for baggage and ticketing arrangements tied to Swiss International Air Lines. If you searched uzwil airport lounge or zkx lounge expecting a departure hall with card-network access, the honest picture is a regional train platform, not a terminal.
The lounge questions that actually apply sit at Zurich Airport (ZRH), roughly an hour away by train and Switzerland's principal international gateway. ZRH runs a genuine lounge network: SWISS operates its own Business and First lounges for premium-cabin travellers and Star Alliance elite passengers, and Priority Pass along with several credit-card programs reach additional spaces across the airport's docks. Card coverage, airline status, and day-pass questions belong to Zurich, not to the station code. Zurich's terminal also includes plenty of independent cafes, restaurants, and shops airside, a reasonable option if your credentials do not reach one of the dedicated lounges themselves.
Whether Uzwil itself participates in any through-check arrangement for luggage or boarding passes with SWISS is worth confirming directly with SBB or your airline before travel, since these station-level partnerships can be added, changed, or withdrawn independent of anything at Zurich Airport. Do not assume the code implies lounge access, food service, or a waiting room built for air travellers; expect an ordinary Swiss regional station instead.
For most people whose journey routes through this code, the sensible plan is simple: treat Uzwil as a rail departure point only, and direct every actual lounge question, which program, which terminal, what hours, at Zurich Airport, ideally by checking SWISS or your card issuer's current lounge directory close to your travel date. Zurich, not Uzwil, is where a real business lounge and its access rules exist.