Blockchain & Web3 Development Company in London

Audit and custody are where a London chain budget actually goes: a scoped smart contract suite at London rates, a custom dApp with wallet integration, institutional custody via Fireblocks or Copper Connect, FCA financial promotion-compliant front end, and Elliptic or Chainalysis monitoring, or tokenisation platforms with permissioned ERC-3643 rails, KYC integration, transfer agent workflow, and tri-party settlement. Scope drivers include Solidity contracts, Foundry test coverage above 95 percent, an internal review, and one external audit pass with a tier-one firm (Trail of Bits, Consensys Diligence, OpenZeppelin, Sigma Prime, or Spearbit). London rates reflect the senior Solidity and protocol engineering market, IR35 off-payroll overhead, and the FCA-aware compliance overhead institutional buyers expect. We give fixed-fee proposals rather than open T and M estimates, and smart contract R&D often qualifies under the April 2024 merged R&D tax relief scheme.

The FCA Cryptoasset Register, administered under the Money Laundering Regulations 2017 as amended in 2020, requires UK cryptoasset exchange providers and custodian wallet providers to register before carrying on business. The bar to pass is high, with approval rates historically under 15 percent, and the FCA publishes a list of unregistered firms it has warned against. Our discovery phase runs the activity test (are you running exchange services between fiat and crypto, crypto and crypto, or operating a machine, or are you a custodian wallet provider as defined in regulation 14A), and if you are in scope we coordinate with FCA-licensed legal counsel to scope the application, prepare the AML business-wide risk assessment, build out the AML programme, document the senior management responsibilities, and stand up the operational systems the FCA expects to see before granting registration. If you are out of scope (pure infrastructure provider, software vendor, or non-custodial protocol) we document the rationale for your board and external counsel.

Since 8 October 2023 the FCA''s cryptoasset financial promotion regime treats most consumer-facing crypto marketing as financial promotion under section 21 of FSMA 2000. Promotions must be communicated or approved by an FCA-authorised person, must carry a prescribed risk warning, must avoid inducements like refer-a-friend bonuses, and must implement a 24-hour cooling-off period and appropriateness assessment for first-time investors. Our work covers the front-end design changes (mandatory risk warning placement and persistence, removal of inducements, cooling-off page state, appropriateness questionnaire flow aligned to FCA expectations), the back-end records (consent capture, appropriateness scoring history, audit log retention to FCA standards), and the operational pattern for either using a section 21 approver, registering with the FCA under MLR 2017, or routing promotions through an authorised firm under a financial promotion approval arrangement. We have shipped this for both FCA-registered cryptoasset firms and overseas exchanges marketing into the UK.

Yes. We integrate against Fireblocks, Copper Connect (the institutional API offering from Copper.co, the London-headquartered custodian), BitGo, Anchorage Digital, and Zodia. Policy engine work covers velocity limits, counterparty allowlisting, time-window restrictions, multi-approver workflows aligned to the segregation of duties expectations FCA supervisors expect to see, and break-glass procedures with NCA SAR reporting workflows. We integrate Copper ClearLoop for tri-party off-exchange settlement where the client trades on Bitstamp, Bitfinex, Bybit, OKX, or Deribit and wants to keep assets in custody rather than on the exchange wallet. We deliver Travel Rule plumbing through Notabene, Sumsub Travel Rule, or 21 Analytics aligned to JMLSG guidance, and we hand over an operational runbook covering daily reconciliation, key ceremony protocols, internal audit evidence, and the documentation FCA SS3/19 third-party risk reviewers expect.

Tokenisation in London has moved from pilot to early production in 2024 and 2025. HSBC Orion has issued digital bonds with the European Investment Bank and tokenised gold for Hong Kong and Singapore institutional clients. Citi Token Services has launched cross-border deposit tokens. The London Stock Exchange Group has proposed a digital markets infrastructure (DMI) for tokenised securities. The Bank of England and HMT have run consultations on tokenised deposits and a wholesale CBDC. M&G and BlackRock have run tokenised money market fund pilots on permissioned rails. ERC-3643 (the permissioned token standard) has emerged as the de facto choice for regulated tokenisation. Our tokenisation work delivers ERC-3643 or alternative permissioned contracts, integration with FCA-registered transfer agents, KYC and accredited investor verification, FCA Digital Securities Sandbox conformance where the client is in the sandbox cohort, and FMI-aligned reporting (where the platform may eventually fall under the Financial Market Infrastructure regime). For UK Gilts tokenisation specifically, we work alongside the issuing agent and the DMO''s evolving guidance on digital issuance.

The UK Travel Rule, in force since September 2023 under the Money Laundering and Terrorist Financing (Amendment) (No.2) Regulations 2022, requires cryptoasset transfers above GBP 1,000 to carry originator and beneficiary information between cryptoasset firms, with JMLSG guidance setting the operational standard. We integrate Notabene, Sumsub Travel Rule, 21 Analytics, or the TRP messaging standard, depending on the client''s counterparty mix. Sanctions screening runs through Elliptic Lens (London-headquartered), Chainalysis KYT, or TRM Labs UK against OFSI consolidated list, OFAC SDN, EU sanctions, and the UN consolidated list. We wire SAR generation into the National Crime Agency NCA SAR Online portal with named MLRO sign-off, document the AML business-wide risk assessment under MLR 2017 regulation 18, and build the customer risk-rating engine the FCA expects to see during a supervisory visit. For wallet screening at deposit and withdrawal, we set sanctions risk thresholds aligned to OFSI expectations and the client''s board-approved risk appetite.

HMRC published its Cryptoassets Manual in 2021 and has updated it through 2024 and 2025. For a UK company holding cryptoassets, gains and losses on disposal generally fall within corporation tax on chargeable gains, with token-for-token swaps treated as disposals at market value. Staking rewards, mining income, and airdrops are taxed as trading income or miscellaneous income depending on activity and intent. DeFi lending and liquidity provision can trigger disposal events under HMRC''s evolving DeFi guidance, and HMT has consulted on a possible reform that would treat certain DeFi positions as non-disposals. Employee token compensation falls within PAYE and NIC where vesting conditions are met, and EMI and growth share planning can apply in narrow cases. VAT on cryptoassets generally follows the CJEU Hedqvist decision, with exchange of crypto for fiat exempt as a financial service, while NFT and tokenised service transactions are evaluated on the underlying supply. We design contract architecture and treasury operations to minimise unintended disposal events, work alongside the client''s tax counsel for opinion-grade rulings, and document transaction flow for the HMRC enquiry the client should expect at some point.

In May 2024 the FCA permitted Recognised Investment Exchanges to list cryptoasset-backed Exchange Traded Notes for professional investors, and the London Stock Exchange listed Bitcoin and Ethereum ETPs from issuers including 21Shares, WisdomTree, and Invesco. Retail access remains restricted under the FCA''s ongoing position. The HMT Crypto Roadmap, the Financial Services and Markets Act 2023, and the FCA''s policy statements through 2024 and 2025 are progressively bringing stablecoin issuance, custody, exchange, broking, lending, and staking into the regulatory perimeter. The Bank of England has consulted on a regulatory regime for systemic payment stablecoins, and the wholesale CBDC programme has progressed through design and consultation. Our work tracks the live FCA consultation papers (CP24/x and CP25/x series), the PRA SS1/24 series, and the Bank of England Discussion Papers, and we update the client''s product roadmap when a phase of the HMT roadmap lands. Founders building in London should expect the regulatory perimeter to keep moving inward through 2026 and 2027, and architecture choices made today should assume eventual FCA authorisation rather than indefinite registration-only status.