Shelter
I LOVE what Shelter has done with their personality. Their brand voice fits in seamlessly.
What’s good about Shelter’s tone of voice guidelines:
They cover what they’re not as well as what they are (sometimes it’s easier to get the point across by saying “We’re not…”).
Their principles are punchy and descriptive. Even without the additional explanation, you could probably get pretty close to replicating their tone of voice.
Their personality ties into their mission.
They’ve separated “tone” and “style.” One of my biggest pet peeves is when people say, “We’ve got a tone of voice guideline document,” for me to then discover it’s only got things like number formats and whether to write out percent. These details are important too, but don’t let them take over — your brand needs a personality as well!
They’re comprehensive and explain how to write for some of their most used channels as well as how to tackle difficult topics (a must given Shelter’s work).