Castle
Automated Bitcoin treasury for small and medium businesses—convert revenue to BTC via payment and bookkeeping integrations.
Why We Recommend Castle
Castle is backed by notable investors including Boost VC, Winklevoss Capital, Park Rangers Capital, and Epoch Ventures, having raised $1 million in a pre-seed round in June 2025. The platform is operated by Orqestra and is headquartered in Miami, Florida.
Castle functions as a software automation layer that connects to existing payment processors and bookkeeping tools rather than holding funds directly. Businesses maintain their existing relationships with exchanges and custodians while Castle automates the treasury strategy. The platform emphasizes transparent pricing with no hidden spreads or fees beyond the stated ~1% transaction fee on the free plan.
Best For
Small and medium-sized businesses seeking to build a Bitcoin treasury without the complexity of manual management. Ideal for restaurants, e-commerce stores, SaaS companies, fitness centers, accounting firms, real estate businesses, and startups that want to allocate a portion of profits (typically 5-10%) into Bitcoin automatically.
Businesses already using payment processors like Stripe, Shopify, Square, or PayPal benefit most, as Castle integrates directly with these platforms to automate Bitcoin purchases based on incoming revenue. Companies using QuickBooks or Xero for bookkeeping can sync their financial data for seamless treasury operations. The platform suits business owners who want responsible, long-term Bitcoin exposure without active trading or aggressive strategies.
Services & Features
- Percentage-of-revenue auto-buys
- Recurring DCA purchases
- Sweep account functionality
- Shopify/Stripe/Square integrations
- QuickBooks/Xero syncing
- Team roles and permissions (Pro)
- API access (Pro)
- ~1% transaction fees
Considerations
Castle is available only to business entities organized and operating in the United States. Individual consumers, advanced traders, and large enterprises are not the target users. The platform focuses exclusively on Bitcoin with no support for other cryptocurrencies. Castle operates as a software automation layer and does not provide detailed public information about its custody model, key management, or security architecture. There is no mention of proof of reserves, third-party audits, or insurance coverage. Lightning Network support is not documented. The platform lacks manual trading capabilities, lending features, tax reporting tools, or advanced analytics. No mobile apps are available—access is web-only. As a newly launched platform (public launch June 2025), there is limited track record and no substantial user reviews available for assessment.
