Day-of logistics calculator
Hotel Block Calculator
Estimate how many rooms to reserve for out-of-town guests so you secure a group rate without overcommitting and triggering costly attrition fees. Adjust the expected uptake and buffer to match your crowd. Once you know where guests are staying, plan how to get them to the venue with the shuttle calculator.
Your room block
Attrition warning
- Most hotel contracts include an attrition clause: if fewer rooms book than you reserve, you can owe the difference. Start with a smaller block (often 80% of your estimate) and ask the hotel to add rooms as they fill — or request a courtesy block with no minimum.
- Estimate assumes ~60% of out-of-town guests book in the block, at 2 guests per room.
- Suggested initial block adds a 10% cushion above the core estimate.
- Reserve blocks at 2–3 hotels across price points and lock a release date (often 2–4 weeks before the wedding).
Treat these as ballpark figures to plan and order against — your venue and vendors will have the exact numbers.
Next: read How Many Hotel Rooms Should You Block for a Wedding? or fold this into a full plan.
Build your wedding planHow this is calculated
- Guests booking = out-of-town guests × expected uptake (default 60%).
- Rooms needed = guests booking ÷ guests per room (default 2), rounded up.
- Total room nights = rooms × nights; suggested block adds a buffer (default 10%).
- Start smaller to avoid attrition penalties, and add rooms as the block fills.
Every figure here is a well-worn planning rule of thumb, not a quote — use it to budget early, then lock in real numbers as you book.
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Open →Frequently asked questions
How many hotel rooms should I block for my wedding?
Estimate how many of your out-of-town guests will actually book (often around 60%), divide by the number of guests sharing each room (usually 2), and round up. This calculator does that math and adds a small buffer so you can suggest a sensible starting block to the hotel.
What is hotel block attrition and why does it matter?
Most contracted room blocks include an attrition clause: if guests book fewer rooms than you reserved, you can be charged for the unsold rooms. That's why it's smart to start with a smaller block — often around 80% of your estimate — and ask the hotel to add rooms as they fill, or request a courtesy block with no minimum.
What is the difference between a courtesy block and a contracted block?
A courtesy block holds a set of rooms at a group rate with no financial obligation — if they don't book, you owe nothing, but the hold is usually smaller and released earlier. A contracted block guarantees more rooms and a locked rate but comes with attrition risk and sometimes a minimum spend.
How far in advance should I reserve a room block?
Reach out to hotels as soon as you have a date and venue, ideally 8–12 months out for popular destinations. Reserve blocks at 2–3 hotels across price points and confirm the release date — the deadline when unbooked rooms return to the hotel — which is often 2–4 weeks before the wedding.
Last reviewed June 2026 by Jared Waterworth. Estimates use widely accepted wedding-planning rules of thumb — see how we estimate. Numbers vary by region, season, and vendor, so verify before you book or buy.