It’s probably safe to say that most people with email addresses are used to having their addresses public. That’s why we barely bat an eye at spam; we’ve accepted it as “normal” (although it’s far from it, but that’s a whole other topic).
Recently, though, calendar spam has also started to pick up speed, and if you are unfamiliar with it, you are not alone. During our February 12, 2026 Office Hours livestream, a viewer reported that a calendar meeting invite had mysteriously appeared in their Outlook account.
Fortunately, it’s not as scary as it sounds and, like all other spam, is easy to deal with. In this edition of our Office Hours Q&A series, we’ll see what calendar spam is, how it works, the dangers it poses, and how to deal with it.
The initial concern about calendar spam
Towards the latter half of the livestream, one of our regular viewers raised an alarming yet curious concern. This is what they said:
A fraudulent PayPal Amazon invoice was added to my Microsoft Outlook calendar as a meeting invite, even though I never approved it.
The event claimed I’d be charged $577.89 for an Apple Magic keyboard and urged me to call a phone number to cancel, which is a common callback scam pattern.
Then they elaborated that they had deleted the meeting and confirmed that their PayPal and Amazon accounts had no such charge. Finally, the auto-accept settings in Outlook were off, yet the meeting still got through. They suspected it arrived as an .ics file and wanted a bit more clarity. Nathan was more than happy to help.
What is calendar spam?
Before we dive into how this might have happened, let’s first talk about what exactly calendar spam is.
The good news is that it’s nothing more than (not so) good, old spam, just in a different format. It’s become more popular in recent years due to advances in AI, enabling malicious actors to be more efficient in their tactics.
The purpose? Phishing. Out of the estimated 376 billion emails sent daily, around 1.2% are phishing, which comes up to 4 billion scam emails per day. Those emails try to impersonate reputable entities like banks or popular services to steal sensitive data like:
Credit card information.
Login details.
Personal details.
They’re always after information that most people would be unwilling to part with, which is why attackers rely on urgency and deceit. These phishing attempts used to be primarily in our inboxes; now they seem to be migrating to our calendars as well.
Why calendar spam hits differently
While we may be used to our inboxes getting flooded with spam, many of us view our calendars as much more private and structured. After all, we use them to organize our daily or professional lives.
When an unexpected meeting invite appears, threatening us with an unwanted action, it feels more personal. It seems more official than usual spam since it ended up in our calendar, our curated, organized space.
Of course, the illusion crumbles the moment you look at the meeting details and realize it’s most likely not what it claims to be. In our viewer's case, and as Nathan confirmed, a quick check of the supposedly affected accounts revealed it to be nothing but a flimsy attempt at a phishing scam.
However, it’s still a scam attempt, and unfortunately, they still work sometimes. That’s why it’s important to know the risks and what to do in such a situation.
Calendar spam risks and what to do
Calendar spam often appears dangerous because it feels intrusive. However, the invite itself is rarely the problem.
That’s why it helps to separate what actually causes harm from how to protect yourself.
The real threat spam hides
If you’ve ever seen any videos online about people exposing scammers (they can be educational and funny), then you know how it works. It typically involves these elements:
A fake support line that pressures you to share personal information.
Remote access to your devices disguised as an attempt to help.
Phishing links that record and steal your login details.
Social engineering (typically through urgency), designed to extract money or sensitive data.
The classic combination is a support line impersonating a company that supposedly charged your card. You call in to get it removed, they get you to install remote access software on your device, and steal your data.
Safeguarding your data from scammers
Fortunately, you don’t need expensive software or to stay off the internet to protect yourself and your data. We recommend two things (technically three):
Adjusting your calendar settings.
Common sense and attentiveness.
Firstly, turn off the automatic processing of invitations to your calendar. Google Calendar and Microsoft Outlook both offer options to keep invites in your inbox. That makes them easier to inspect and doesn't automatically clutter your calendar. The caveat is that this doesn’t always work when you receive an .ics file directly.
An .ics (iCalendar) file is the standard file type used for calendar events. They contain the event’s details (title, date & time, location, etc.), and some calendars may process them without asking.
Secondly, thoroughly inspect the invite. Do not click on any links or call any numbers, however. Hovering over a link is fine; it shows you where it goes (typically at the bottom left of your browser window). Instead, ask yourself these questions:
Do you recognize the sender?
Is the event being mentioned one you anticipated?
Do any of the links or phone numbers look strange?
Is it from an entity that you associate/have an account with?
Asking these questions should help you determine if the invite is legitimate. Of course, many invites put pressure on you to act quickly and without thinking. That’s a huge red flag.
What you can do instead is use the entity's official communication channels and contact them there for more information, not through the invite directly. For example, if you receive one for a fraudulent PayPal charge, as it happened with our viewer, go to PayPal’s site directly, check your balance, and if necessary, talk to their support from there.
Spam is an ongoing battle you can mostly ignore
Whether it’s inbox or calendar spam, most people ignore or dismiss it because that’s the best way to deal with it. Calendar spam is a bit more annoying because attackers know people trust their calendars.
However, it’s just a matter of time until people learn how to deal with such invites, as they do with spam emails, after which it becomes just another thing to filter out. That’s why we wanted to raise awareness with this blog, inspired by the question from our viewer.
Calendar spam is something people don’t think to ask about until it happens to them. If it’s happened to you and you have a question about it or websites, hosting, or agencies, register for our weekly Office Hours. Join Nathan Ingram and our community, and get your questions answered live.
FAQ
Can just opening a calendar invite without clicking any links compromise my device or account?
In almost all cases, simply viewing a calendar event is safe. The danger lies entirely in the actions the invite tries to prompt: calling a phone number, clicking a link, or downloading and opening an attachment. The same is true for .ics files: the file format itself is just structured plain text and doesn't execute code when opened.
The practical takeaway is that looking at an invite to assess it is always safe; interacting with its contents (links, numbers, attachments) is where the risk lives.
How do scammers get their calendar invites into my calendar in the first place, if I never accepted anything?
There are a few routes, and the blog's viewer encountered one of the more subtle ones. Many calendar applications historically auto-accepted invites from anyone, since calendar sharing was designed as a collaborative, open tool. Some apps also process .ics files attached to emails automatically, adding the event without any explicit user action. Additionally, if someone has your email address, they can send a calendar invite to it just as easily as an email, no hacking required.
Routing invites to your inbox for manual review rather than auto-accepting trades a small amount of convenience for significantly less calendar clutter from strangers.
Are there warning signs in a calendar invite that distinguish a scam from a legitimate scheduling request?
Several. Legitimate calendar invites from businesses or services you actually use will almost always come from an email address that matches the company's domain. Scam invites frequently come from free email services, randomly generated addresses, or domains that superficially resemble well-known brands.
The event description is another tell: legitimate invites describe a meeting or appointment, while scam invites typically contain urgent financial claims, alarming charges, or instructions to call a number or click a link.
If I accidentally called the number in a calendar spam invite but didn't give any information, do I need to take any action?
Calling the number and immediately hanging up, or calling and saying nothing, is very low risk. The main concern with callback scams is the social engineering that happens once you're on the line: the pressure to provide personal details, confirm financial information, or install remote access software. If none of that occurred, your exposure is minimal.
However, it's worth being aware that scammers sometimes note which numbers receive callbacks, as that confirms to them that the number is active and belongs to someone responsive, meaning you may receive follow-up contact through other channels.