To fix Mac Internet Sharing not working, first verify that the Mac itself can use the intended upstream connection. Then open System Settings > General > Sharing (System Preferences > Sharing on macOS Big Sur), choose the working connection under Share your connection from, and select a different output under To devices using, with Wi-Fi security and a strong password when Wi-Fi is the output. If a VPN or Wi-Fi entry is missing from those lists, share the Mac's underlying connection and confirm the output hardware is recognized. If sharing still fails, classify whether it will not turn on, is invisible, rejects clients, connects without internet, or disconnects.

Key Takeaways

Internet Sharing forwards one Mac network connection through another interface.

It is not iPhone Personal Hotspot, Wi-Fi password sharing, File Sharing, or Screen Sharing.

The upstream from interface and downstream to devices using interface must be selected deliberately.

Keep the firewall enabled; do not use pfctl, hand-built NAT or routes, or delete sharing configuration.

Test VPNs and network filters only when timing implicates them, and make the comparison reversible.

Apple documents Internet Sharing in current macOS through General > Sharing.［1］ If you are not sure which layer failed, start with the device and app troubleshooting guide.

Which Mac sharing feature do you need?

Several Apple features sound similar but solve different problems:

Feature	What it does
Internet Sharing	Shares one Mac network connection through another interface
Personal Hotspot	Shares an iPhone or cellular iPad connection
Wi-Fi password sharing	Sends saved Wi-Fi credentials to another Apple device
File Sharing	Makes selected Mac files available on a network
Screen Sharing	Lets another device view or control the Mac desktop

Turning on File Sharing will not create an internet hotspot. Likewise, seeing an iPhone Personal Hotspot near the Mac does not mean macOS Internet Sharing is configured.

Internet Sharing has two sides. Share your connection from is the working upstream. To devices using is how clients reach the Mac. Apple warns against choosing the same connection for both sides because doing so can disrupt the network. For example, share Ethernet to Wi-Fi, or another supported input to a separate output.

Verify the Mac's upstream connection first

Before enabling sharing, test the Mac itself.

Open two unrelated websites or services on the Mac.
Confirm which service in System Settings > Network carries that traffic.
Complete any trusted captive-portal sign-in.
If using an adapter, dock, or phone connection, confirm it remains connected.
If every device on the source network fails, troubleshoot the router or provider.

If the Mac is on Wi-Fi but has no internet, follow the Mac no-internet guide. A Mac cannot forward internet that it does not currently receive.

Do not confuse a green or connected status with a working upstream. Test actual destinations. If only one app or website fails on the Mac, fix that narrower service issue before changing Internet Sharing.

On networks controlled by an employer, school, hotel, or provider, sharing may be restricted by policy or terms. Do not bypass those controls. Ask the administrator or operator whether connection sharing is allowed.

Configure the input and output interfaces

Open Apple menu > System Settings.
Select General > Sharing.
Turn on Internet Sharing, then click Configure (or the information control beside it).
Under Share your connection from, choose the tested upstream service.
Under To devices using, select one or more supported, different output interfaces.
If Wi-Fi is selected, open Wi-Fi Options, set the network name, security, password, and any supported channel choice.
Click Done, then confirm that Internet Sharing stays on.

Apple's current instructions turn the service on, open Configure, and then select the source, the output ports, and Wi-Fi details when used. The exact labels can vary slightly across macOS versions and hardware.

Use a strong password and the strongest compatible security option offered. Do not create an open network for convenience. If a very old client cannot join modern security, that is a client compatibility problem; weakening protection for every nearby device is not the safe default.

If your Mac runs macOS Big Sur

Apple's macOS Big Sur guide uses Apple menu > System Preferences > Sharing, then Internet Sharing in the service list. The output list is labeled To computers using, and you start the service by selecting the Internet Sharing checkbox and confirming Start.［2］ The input and output logic is the same as in current macOS.

If a VPN or Wi-Fi entry is missing from the lists

If your VPN does not appear under Share your connection from, choose the underlying connection the Mac actually uses, such as Wi-Fi or Ethernet. Do not assume that devices joining the shared network inherit the Mac's VPN: whether shared traffic is covered depends on the VPN software, so check its documentation and verify each client separately.

If Wi-Fi or another output is missing or cannot be selected, check whether it is also the selected source; the two sides must be different connections. Then confirm the hardware is recognized and not already occupied by an incompatible role. A USB or Thunderbolt adapter should appear as a usable network service before Internet Sharing can depend on it.

Why will Internet Sharing not turn on?

If the switch remains off, turns off immediately, or configuration cannot be saved:

Recheck that the selected upstream exists and is connected.
Make sure the same interface is not selected as both input and output.
Confirm the output interface is enabled and recognized.
Restart the Mac after a normal macOS or adapter-state issue.
On a managed Mac, check whether organization policy disables sharing.
Disconnect and reconnect a dock or adapter once, then verify its Network entry.

Do not use pfctl, manually create NAT or routing rules, unload system services, or delete preference files. Those actions are version-sensitive, can damage unrelated networking, and remove evidence about the original failure. Do not paste Terminal commands whose side effects you cannot explain and reverse.

The macOS firewall is not a reason to disable all protection. Apple notes that sharing services can open access for specific services while the firewall remains enabled.［3］ Keep the firewall on and use supported Sharing controls.

If the shared Wi-Fi network is not visible or clients cannot join

For a network that does not appear:

Confirm Internet Sharing still shows on.
Confirm Wi-Fi is selected under To devices using.
Move the client close to the Mac for the first test.
Review the Wi-Fi name, security, and supported channel settings.
Compare a second client to separate Mac output from one client's compatibility.

For a network that appears but rejects the password:

Reopen Wi-Fi Options and verify the exact current password.
Forget the saved network on the client.
Join again without reusing an old credential.
Keep modern security enabled.
Test whether another client can join.

If only one client fails, focus on that device's saved profile, radio support, software state, and time settings. If every client fails, focus on the Mac's output configuration.

Do not confuse AirDrop or peer-to-peer discovery with an Internet Sharing network. A device appearing in AirDrop proves neither hotspot visibility nor internet forwarding.

Why do clients connect but have no internet?

A joined Wi-Fi network proves only the downstream association. Work back through the path:

Retest the upstream directly on the Mac.
Confirm Share your connection from still points to that service.
Disconnect and reconnect one client after correcting the source.
Test two unrelated destinations from the client.
Compare a second client if possible.

If the Mac itself cannot get online, stop troubleshooting the shared output. If the Mac works but every client fails, turn Internet Sharing off and on once after verifying the configuration, then restart the Mac if needed.

If only hostnames fail, DNS may be involved, but changing DNS is not a universal fix. Preserve the baseline and use the Mac DNS guide only when evidence points to name resolution. Similarly, a proxy should be reviewed through the Mac proxy guide, not deleted at random.

If Internet Sharing is unstable

Observe whether the input, output, or Mac state changes at the same time:

Does the upstream connection disconnect?
Does the Mac sleep, lock, switch network services, or lose an adapter?
Do all clients drop together or only one?
Does the failure begin after a dock or USB cable moves?
Does a crowded wireless environment affect visibility or stability?

Keep the Mac awake and powered during a controlled test. Use one client, pause large transfers, and avoid changing multiple settings simultaneously. If all clients drop when the input changes, stabilize the input. If the input remains good and every client drops, collect the macOS version, hardware model, interface names, adapter details, and timestamps for Apple or the adapter vendor.

Apple notes that third-party VPN, firewall, antivirus, parental-control, and content-filter software can affect network connectivity.［4］ That does not make them the default cause. If the failure starts exactly when one product is enabled, use its supported pause or disconnect control for one brief test, record the result, and restore it. On a managed Mac, involve the administrator. Do not uninstall protection or disable the macOS firewall globally.

Mac Internet Sharing not working after these checks: safe escalation

If supported settings still fail, choose an alternative path that preserves the system:

Use a dedicated router or access point when you need a durable shared network. If you were sharing a hotel or rental connection, compare a travel router with per-device VPN apps before buying hardware.
Use a supported USB tethering path when only one computer needs a phone connection.
Ask the network owner whether sharing is prohibited.
Update macOS and adapter firmware through official channels.
Provide support with input/output selections, exact symptom class, client comparison, and timing.

Do not delete network services or sharing preferences as a trial. If a broader network reset or configuration removal is proposed by trusted support, record DNS, proxies, VPNs, managed profiles, and adapter settings first and understand what will be rebuilt.

Summary

Mac Internet Sharing works only when a valid upstream connection is forwarded through a different, supported output interface. Confirm you are using Internet Sharing rather than Personal Hotspot, password sharing, or File Sharing; verify the Mac's own internet; configure the from/to selections; and preserve Wi-Fi security. Keep the firewall enabled and avoid pfctl, custom NAT, routes, preference deletion, and broad security removal. Escalate with clear input, output, client, and timing evidence.

FAQ

Where is Internet Sharing on a Mac?

Open System Settings > General > Sharing, then select the configuration control beside Internet Sharing.

Internet Sharing vs Personal Hotspot: are they the same?

No. Internet Sharing forwards a Mac connection. Personal Hotspot shares a cellular connection from an iPhone or cellular iPad.

Can I share Wi-Fi to Wi-Fi from a Mac?

Available input and output combinations depend on the Mac and adapters. Do not select the same interface for both sides; use a distinct supported output or dedicated hardware.

Why can clients see the network but not join?

They may have a stale saved password, incompatible security or channel support, or another client-specific problem. Forget the network and retry with the current details.

Why do clients join but have no internet?

The chosen upstream may be wrong or offline. Test internet on the Mac and confirm Share your connection from points to that working service.

Should I turn off the Mac firewall?

No. Keep it enabled. Use the supported Sharing settings; globally disabling the firewall increases risk and does not isolate the fault.

Why is my VPN missing from Internet Sharing, and can it break sharing?

The source menu may not offer a VPN as a separate entry; share the underlying connection and check the VPN's documentation for shared-traffic support. A VPN or network filter can also affect connectivity, but it is not automatically the cause. Test only when timing implicates it, use the product's supported control, and restore the original state.

Should I use Terminal commands to rebuild sharing?

Not for routine troubleshooting. Avoid pfctl, custom NAT or routes, service unloading, and preference deletion unless Apple or an administrator gives version-specific, reversible instructions. AethoVPN does not configure macOS Internet Sharing, NAT, or the receiving device's IP address; diagnose the shared interface before testing any VPN route.

Sources

Apple Support - Share the internet connection on Mac with other network users — https://support.apple.com/guide/mac-help/mchlp1540/mac
Apple Support - Share the internet connection on Mac with other network users (macOS Big Sur 11) — https://support.apple.com/guide/mac-help/share-internet-connection-mac-network-users-mchlp1540/11.0/mac/11.0
Apple Support - Change Firewall settings on Mac — https://support.apple.com/en-gb/guide/mac-help/mh34041/mac
Apple Support - If your device has network connectivity issues, check for VPN and other third-party security software — https://support.apple.com/en-la/102281

Sources checked 4 October 2026.

Mac Internet Sharing Not Working: What to Check