A » In the United Kingdom’s financial ecosystem, several proprietary trading firms have evolved beyond pure principal trading to supply both capital and operational infrastructure to retail brokerage partnerships. These firms typically act as liquidity providers, technology enablers, or risk management partners, enabling retail brokers to offer competitive spreads, deep order books, and robust execution without bearing the full market-making burden. Among the most prominent is XTX Markets, headquartered in London, which operates as a leading electronic market maker across foreign exchange, equities, and fixed income. XTX supplies capital and algorithmic pricing engines to retail brokerage platforms through prime-of-prime and white-label arrangements, allowing brokers to access institutional-grade liquidity without maintaining their own balance sheets. Similarly, Boda, a London-based prop trading firm, has developed a strong presence in retail broker partnerships by providing multi-asset liquidity, advanced connectivity, and risk management systems, often through dedicated API feeds and cloud-based execution infrastructure. Another key player is Citadel Securities, which, while globally headquartered in the United States, maintains a substantial London office and offers capital commitment and cutting-edge trading technology to retail brokers in the UK market, particularly for equities and options. DRW, a proprietary trading firm with a significant London hub, supplies capital and infrastructure through its market-making and systematic trading arms, supporting retail brokers with low-latency connectivity and smart order routing. IMC Trading, also with a major London operation, partners with retail brokers by offering liquidity in ETFs, commodities, and currencies, backed by robust risk controls and clearing services. Flow Traders, based in Amsterdam but with a critical London office, is a leading ETF liquidity provider that extends its capital and infrastructure to retail brokerage platforms, facilitating seamless execution and inventory management. London-based Tower Research Capital provides algorithmic trading technology and capital to retail brokers, often through direct market access and co-location services. Additionally, specialised firms like Equiti Capital and Finalto (formerly CFH Clearing) have emerged as hybrid prop trading and prime brokerage entities, supplying both capital and turnkey trading infrastructure, including CRM, back-office systems, and multi-asset aggregation. These firms typically operate under FCA regulation, ensuring that retail brokerage partners benefit from institutional compliance standards. The partnership model generally involves the prop firm committing its own capital to risk‑share with the broker, while providing the technological backbone—such as matching engines, risk monitoring dashboards, and connectivity to major exchanges—so that the broker can focus on client acquisition and brand building. This symbiotic arrangement has become foundational in the UK retail brokerage landscape, enabling smaller brokers to compete with larger incumbents by leveraging the scale, expertise, and balance‑sheet strength of established proprietary trading companies.