Out of office replies are the bane of the email marketer's life - send a large campaign, and a flood of OOOs hits the inbox behind your marketing platform. There are technical ways to filter them out, but doing so throws away something genuinely useful.
Key findings
- OOOs often reveal whether a contact has left a business, and surface a mobile number or alternative contact for the BD team.
- They help identify the right replacement contact when someone's moved on.
- Most OOOs are now triggered automatically before reaching the inbox, so they're not counted as genuine engagement by mailbox providers anyway.
Why They're Worth Keeping
As Campaign Director Jess Milham at Propeller Group puts it, out of offices are "gold dust" for a BD team - not just confirming a prospect is away, but often capturing a mobile number that enables direct follow-up, and identifying the right alternative contact if someone's left the business entirely. They also tell you who not to keep emailing, which matters for protecting your sender domain reputation.
A Technical Note
Most OOOs today are triggered automatically before they even reach the recipient's inbox - so despite technically being a "reply," mailbox providers generally don't treat them as genuine engagement. Worth bearing in mind if you're trying to read engagement signals accurately rather than just clearing inbox clutter.
Frequently Asked Questions
Why are out of office replies useful for business development?
They often reveal whether a prospect has left the company, surface a mobile number or alternative contact, and confirm who not to keep emailing - all valuable for keeping outreach accurate and effective.
Do most out of office replies count as genuine email engagement?
No. Most are now triggered automatically before ever reaching the recipient's inbox, so while technically a 'reply,' mailbox providers generally don't count them as real engagement.
Andrew Nicholson
Co-founder & CEO at Kulea. Guest lecturer in digital psychology and behavioural economics at the University of Buckingham.