Find The Best Plan For You

WindowSill+ is designed for individual users who want AI-powered text assistance features like translation, spell check, tone adjustment, and custom prompts. WindowSill Pro is built for teams and enterprises. It includes everything in WindowSill+ lifetime, along with organization management features like a standalone installer for easier deployment, members management, AI providers allow-list, usage statistics and more.

WindowSill Pro uses a standalone installer (.exe) instead of the Microsoft Store to give IT administrators full control over deployment. This allows organizations to deploy WindowSill across their fleet using their existing software distribution tools (like SCCM, Intune, etc.), manage updates on their own schedule, and ensure compliance with corporate policies. See our documentation for more details.

Yes, you can switch between monthly and annual billing at any time. For WindowSill+, you will need to cancel your subscription on your Microsoft Account first, then get the annual subscription from the WindowSill settings. For WindowSill Pro, you can switch from monthly to annual using the dashboard and you'll receive a prorated credit for any unused time. If you switch from annual to monthly, the change will take effect at the end of your current billing period.

Yes! WindowSill+ and WindowSill Pro offer a 1-week free trial so you can experience all the AI-powered features before committing. You can start your trial from the dashboard.

WindowSill+ subscribers (monthly or annual) get access to the built-in WindowSill+ AI provider. No API key required, just install and start using AI features immediately. They can also bring their own API keys if preferred.

WindowSill+ lifetime purchasers and WindowSill Pro users need to bring their own API keys (BYOK) from providers like OpenAI, Anthropic, or use local LLMs.

Yes! With any WindowSill+ plan (monthly, annual, or lifetime) and WindowSill Pro, you can connect your own API keys from providers like OpenAI, Anthropic, Google, and others. You can also use local LLMs for enhanced privacy. This gives you full control over your AI usage and costs.

WindowSill Pro uses graduated pricing — the first users are charged at the base rate, and additional users beyond each tier threshold are charged at progressively lower rates. You can add or remove users at any time through your organization dashboard. When you add users, you'll be charged a prorated amount for the remainder of the billing period. Each tier charges its own rate, so adding users only affects the cost of additional seats. See the graduated pricing table above for full details.

Yes. You can join as many organizations as you need. Each one keeps its own settings, members, and extensions, and you can switch between them at any time in the dashboard and directly in the WindowSill app.