Short answer: yes—Macs can get viruses, though true self-replicating “viruses” are rare today compared with trojans, adware, spyware, backdoors, and ransomware. macOS has strong built-in defenses, but those defenses aren’t magic. Understanding what Apple already does for you—and what you should do—will keep your Mac fast, private, and safe.

How macOS protects you (built-in layers)

Gatekeeper + Notarization. When you download an app from outside the Mac App Store, Gatekeeper checks that it’s from an identified developer and notarized by Apple (scanned on Apple’s servers for known malicious content). It also ensures the app hasn’t been altered and asks for your approval the first time you open it. 

XProtect & remediation. macOS includes XProtect, Apple’s signature-based malware detection. In modern macOS, XProtect also includes remediation—if known malware slips in, the system can automatically remove it. 
Since 2022, Apple has added XProtect Remediator, a background scanner that runs periodically to look for specific malware families and clean them up—replacing the older Malware Removal Tool (MRT). 

Runtime protections. System Integrity Protection (SIP) locks down system locations so even admin-level malware can’t easily tamper with the OS. Apps also run with hardened runtime and sandboxing to limit damage if something goes wrong. 

Encryption. FileVault encrypts your disk so data stays protected if your Mac is lost or stolen. (On Apple silicon and T2-equipped Macs, storage is always hardware-encrypted; FileVault adds user-auth protection.) 

For high-risk users: Lockdown Mode (macOS Ventura or later) reduces attack surface against mercenary spyware by sharply limiting certain features. It’s optional and intended for people at elevated risk. 

These layers are robust—but not infallible. You’ll still see Mac malware in the wild, usually spread through fake installers, pirated apps, malvertising, or cleverly abused developer processes.

Real-world examples (yes, it happens on Macs)

• KeRanger ransomware (2016): Attackers trojanized the Transmission BitTorrent installer; it was even signed with a legitimate Developer ID. Apple revoked the certificate and updated XProtect, but the incident showed that signed apps can still be abused. 

• Shlayer notarization slip (2019): A Shlayer adware build was briefly notarized by Apple, allowing it to pass Gatekeeper until Apple blocked it—proof that notarization greatly helps, but attackers do probe its edges. 

• EvilQuest/ThiefQuest (2020): Ransomware with spyware capabilities spread mainly via pirated software installers—illustrating how high-risk “cracks” are a common infection vector on macOS.

What actually infects Macs today?

• Adware & grayware: browser hijackers, push-notification spam, and “cleaner” apps that over-promise.

• Trojans & backdoors: disguised as “Flash updates,” cracked apps, or droppers that fetch payloads later.

• Stealers/spyware: attempt to grab passwords, cookies, or crypto wallets; often delivered via phishing pages.

• Ransomware: rarer on macOS but very real, mostly via untrusted downloads.

The common thread is social engineering: persuading you to install or approve something.

15 practical ways to protect your Mac

1. Keep macOS and apps up to date. Apple routinely improves Gatekeeper, XProtect, and remediation. Install macOS updates promptly. 

2. Leave Gatekeeper on (default). Don’t disable it or habitually click Open Anyway. If you must run an unsigned tool, understand the risk and the source. 

3. Prefer the Mac App Store or well-known developers. Outside the Store, look for a reputable vendor and a notarized build. (Developers distribute with Developer ID plus a notarization ticket so Gatekeeper can verify integrity.) 

4. Be picky with downloads. Avoid “free” video converters, pirated apps, and fake codec updaters—classic malware bait in the Mac world.

5. Scrutinize installers. If an installer demands a profile, kernel/system extension, or excessive permissions, pause and verify. Many modern tools use safer system extensions or no extensions at all.

6. Review browser extensions. Remove anything you don’t recognize; extensions can read and change site data.

7. Use a standard account for daily work (or at least avoid typing your admin password for unknown software). Least privilege reduces impact if something goes wrong.

8. Enable FileVault. Protects data at rest and adds a barrier to offline tampering. 

9. Turn on “fraudulent website” warnings in your browser and distrust pop-up “Your Mac is infected—download this” messages. Close the tab; don’t click.

10. Check Login Items and background agents after installing new apps. Remove items you don’t need (System Settings → General → Login Items). Unexpected persistence is a red flag.

11. Back up with Time Machine plus an off-site or cloud backup. Ransomware can encrypt files; backups are your safety net. (Keep at least one backup not always connected.)

12. Use strong, unique passwords + 2FA (iCloud Keychain is fine). Credential theft is a bigger risk than classic viruses for many people.

13. Keep “Install system data files and security updates” enabled so Apple can update XProtect and remediation components in the background. 

14. Consider Lockdown Mode if you’re a journalist, activist, or handle sensitive investigations. It intentionally breaks some features to shrink attack surface. 

15. Add reputable endpoint protection if your risk is higher (business/regulated environments) or you want extra visibility. Apple’s layers are strong, but a second set of eyes can catch adware or novel threats sooner. (Enterprises often pair macOS defenses with EDR.)

How to tell if your Mac might be infected

• Sudden floods of ads or your search engine keeps changing.

• New login items you didn’t add; browser extensions you don’t recognize.

• High CPU/network use at idle (check Activity Monitor → CPU/Energy).

• Security prompts for tools you didn’t install.

First steps:

1. Update macOS (pulls the latest XProtect/remediation). 2) Remove suspicious login items and extensions. 3) If symptoms persist, run a scan with a reputable Mac anti-malware tool or contact Apple Support. XProtect Remediator will continue to run periodic background scans and can clean many families automatically. 

Do you need antivirus on a Mac?

Apple’s layered approach—Gatekeeper, Notarization, XProtect with remediation, SIP, sandboxing, FileVault—gives you excellent baseline protection. Still, human behavior (what you install; what you click) matters most. Many home users do fine with Apple’s defenses plus careful habits; others prefer a lightweight anti-malware for extra peace of mind and on-demand scans. Mac-focused outlets echo this balanced view: built-ins are good, but an added tool can help if you want more visibility or you often install third-party software. 

Quick-reference checklist

• Keep macOS/apps updated and security data files enabled. 

• Leave Gatekeeper on; install from trusted sources only. 

• Turn on FileVault; use strong passwords + 2FA. 

• Audit Login Items and browser extensions after new installs.

• Maintain versioned backups (Time Machine + off-site/cloud).

• If you’re high-risk, consider Lockdown Mode. 

Bottom line

Macs aren’t immune—there’s a long, well-documented history of Mac malware, from KeRanger ransomware to adware like Shlayer that briefly slipped past notarization. 

The good news is that Apple’s security architecture keeps improving, with Gatekeeper + Notarization at the front door and XProtect (with remediation) and SIP patrolling inside. Pair those layers with smart habits, and you’ll dramatically reduce your risk while keeping your Mac fast and trustworthy.