How to find a meeting time with someone at another company (without sharing calendars)

Inside one company, finding a meeting time is a solved problem: the calendar shows everyone's free/busy and picks a slot. Across two companies, none of that works, because free/busy visibility stops at the organisation boundary — so scheduling with a client or a partner still means email ping-pong. There are four ways around it: have both IT teams federate free/busy (rare, admins only), send a booking link (one-way — they pick from your slots), swap typed-out times (the ping-pong itself), or overlay each other's real availability with a link that shows busy/free and nothing more. The last one is the only approach where you can actually seewhen you're both free.

Why the boundary exists

Google Workspace and Microsoft 365 both let colleagues see each other's free/busy by default. That visibility is scoped to the tenant — the organisation's own account. Someone at another company is, to your calendar, a stranger, and their calendar is invisible no matter how much you work together. Even when both companies use the same provider, the two tenants don't talk.

Option 1: Free/busy federation between the two tenants

Both providers support an administrator-level setup that lets users in one organisation see free/busy in another. When it's in place, cross-company scheduling works exactly like internal scheduling.

It almost never is. It needs an administrator at bothcompanies to agree and configure it, per partner organisation. For a long-term strategic partner with aligned IT teams, ask. For a client you started working with last month, it isn't going to happen.

Option 2: Send a booking link

A booking page moves the decision to the other person: here are my slots, pick one. It removes the back-and-forth and is the right tool when the relationship is asymmetric — a prospect booking a sales call, a candidate booking an interview.

It is one-directional by design. You've told them when you are free; you still know nothing about when theyare. With a peer at another company, that's the wrong shape — and plenty of people feel that a booking link sent to a peer or a senior contact reads as being processed rather than scheduled with.

Option 3: Type out times and trade emails

The default, and it's fine for a one-off. Offer three ranges, name the timezone, wait. The cost shows up on repeat: each round trip takes a day, the slots you offered are gone by the time they answer, and the meeting lands a week later than it needed to. Our guide to sending availability in an email covers how to do this well when it's the right choice.

Option 4: Overlay each other's real availability

The approach that actually shows both sides: each person has a link that displays their real free/busy — as coloured blocks on a week grid, in the viewer's timezone, with no event titles, attendees or locations. Send yours; ask for theirs. When you open theirs and merge it with your own view, you'll see when you're both free, laid over each other, across companies and across calendar providers — one of you on Google, the other on Outlook, doesn't matter.

From there you propose a time or book a slot directly, and it lands for their approval. If they do the same with your link, they get the same overlay from their side. Neither company's IT is involved and neither calendar was shared — only when each of you is busy.

BusyBoard is the automated way here: connect your calendars, send your link, click Merge with My Calendaron theirs, and you'll see when you're both free. The same overlay works for a group — three people at three companies is no harder than two.

Which to use when

• Long-term partner, cooperative IT on both sides: ask for free/busy federation once and enjoy it forever.
• Asymmetric — they book you: a booking link.
• One-off with someone important: type the times, add a link underneath as the fallback.
• A peer you'll schedule with repeatedly: overlay availability. It is the only option where both schedules are on the screen at once.