Which ATS has good email and calendar integration?
You can spot good integration by three things. First: the ATS sends email from your company's own domain, so the candidate receives the message just as if the recruiter had sent it from Outlook or Gmail. Second: the system can sync communication with the candidate – there are three technical models, and they differ mainly in how much mailbox access you give the system. Third: the calendar works both ways – the ATS sees free slots including colleagues' shared calendars, and a scheduled interview writes back into Google Calendar or Outlook, including a Google Meet or Teams link. The top tier is then a booking link that lets the candidate pick a slot with no risk of a clash.
The basics: sending from your domain
This isn't cosmetic. When the ATS sends candidates messages from an unfamiliar address, the candidate doesn't recognize the sender, the reply gets lost, and deliverability drops. So the system has to be able to send under your domain – as if the email had gone out straight from Outlook or Gmail.
The most common route is to connect a specific email account via authorization, from which messages go out. So verify with the vendor that the integration works with Microsoft 365 (Outlook) and Google Workspace (Gmail).
There's also a variant where the ATS connects directly to your company's email servers using SPF and DKIM records. But that gives the vendor's server the right to send practically any email under your domain, and from a security standpoint it therefore tends not to be preferred.
Related features: Sending from your own domain · Email templates
Three ways to sync communication with the candidate
The goal is for the whole conversation with the candidate to stay in the ATS – including what the recruiter wrote from their own mailbox and what the candidate replied. This can be achieved in three ways. They're not equal.
| Model | How it works | Advantage | Disadvantage |
|---|---|---|---|
| 1. Plugin (manual) |
An add-in in Outlook or Gmail with which the recruiter saves a chosen conversation into the ATS – or creates a candidate straight from an email. | Full control over what gets saved. The cleanest for security. | Depends on the recruiter's discipline. What they don't save isn't in the system. |
| 2. System |
The ATS has its own address that you put in copy. Everything that passes through it is recorded on the candidate. | Works automatically, and the system has no access to your mailbox. | Records only what passes through copy – and the address in copy can be removed manually. |
| 3. Direct mailbox connection |
The ATS connects to the mail account and reads all incoming messages. | Nothing slips through, the recruiter has to do nothing. | A security risk. Most companies won't allow it from a cybersecurity standpoint. |
Related features: Communication sync · Outlook plugin · Gmail plugin
The calendar has to work both ways
Calendar integration is often reduced to "I see my meetings in the ATS". That's not enough. Useful integration has two directions.
Direction 1: the ATS sees availability – including colleagues'
The system reads not just your calendar but also the ones you have shared in Outlook or Google Calendar. When scheduling an interview you can transparently see when the hiring manager and another panel colleague are free, and propose a time correctly the first time.
Direction 2: an interview from the ATS writes back into the calendar
When you create an interview in the ATS, the event appears in the chosen calendar (or several at once) and a standard invitation goes out from it. For an online interview the system immediately generates a meeting link – Microsoft Teams with Outlook, Google Meet with Google – and inserts it into the invitation.
The result is that in the ATS you have a clear list of interview times, a direct call link for an online meeting, and the branch address for an in-person interview where the candidate should arrive.
Related features: Google Calendar · MS Outlook calendar · Availability of free slots · Writing a time back into the calendar · Teams / Meet link generation · Interview date
Booking links: let the candidate pick a time
Instead of email ping-pong along the lines of "would Thursday work for you?", send the candidate a booking link. It's tied to your calendar and follows rules you set – how long the slot is, the earliest and latest you can book, and the buffer between interviews.
The candidate picks a time that suits them, and you're guaranteed it will never clash with another event in your calendar. More advanced variants can also factor in several external calendars at once, or create a multi-slot where several candidates sign up for one time – typically for an assessment center.
Booking links are becoming standard. To a candidate they signal that the company is technically mature and that it builds hiring around their convenience, not the recruiter's.
Related features: Booking links · Connecting multiple external calendars · Multi-slots for an assessment center
The complete list of questions for an ATS vendor →
This guide is published by Recruitis.io, an ATS. How we handle integration:
- We connect to Microsoft 365 (Outlook) and Google Workspace (Gmail) – you authorize a specific email account and we send from it under your company's own domain.
- Of the three sync models we offer the first two: an Outlook and Gmail plugin (manually saving a conversation or creating a candidate straight from an email) and a system email address in copy that records communication between recruiter and candidate.
- The calendar we connect two-way: you see your own availability and colleagues' shared calendars, and a scheduled interview writes back into the calendar. For an online meeting a Teams or Google Meet link is generated into the invitation.
- Booking links let the candidate pick a free slot by your rules, with no risk of a clash.
What we deliberately don't do: the third model – a direct connection to your mailbox, where the ATS would read all incoming messages – we don't offer. Most companies won't allow it for security reasons anyway, and we don't want access to your mail.
And on the system email, straight up: we add the system address to copy automatically every time you send an email from the system – even when you just hit "reply" (you don't have to "reply all"). The recruiter doesn't have to think about it. But only what passes through copy is recorded: the address in copy can be removed manually by both recruiter and candidate.
Frequently asked questions
How does syncing email communication with a candidate work in an ATS?
There are three models, and they're not equal. The first is a plugin in Outlook or Gmail, with which the recruiter manually saves a chosen conversation into the ATS, or creates a candidate straight from an email; it gives full control and is the cleanest for security, but it depends on the recruiter's discipline. The second is a system email address: the ATS has its own address that the system automatically adds to copy when sending, so the communication is recorded on the candidate; it works automatically, the recruiter doesn't have to think about it, and the system has no mailbox access. But only what passes through that copy is recorded, and the address in copy can be removed manually. The third is a direct mailbox connection, where the ATS reads all incoming messages; from a cybersecurity standpoint it tends to be unpopular and most companies won't allow it.
What are booking links for scheduling interviews?
A booking link is a link tied to the recruiter's calendar that you send the candidate instead of arranging a time over email. It follows rules you set: slot length, the earliest and latest possible time, and buffers between interviews. The candidate picks a time that suits them, and the system guarantees it won't clash with another event in the calendar. More advanced variants can factor in several external calendars at once, or create a multi-slot where several candidates sign up for one time, typically for an assessment center. Booking links are becoming standard, and to a candidate they signal that the company is technically mature.