Why AirPrint Won’t Connect and How to Fix Firewall and Router Blocking

Joe B.

Reviewed for technical accuracy

Specialities: Windows 11/10, macOS (Sonoma/Ventura/Monterey), Printers, Networking, Office Equipment

AirPrint not connecting on iPhone, iPad, or Mac — Bonjour blocked, mDNS/IGMP/ports, AP isolation, same subnet/VLAN

Technician

Hey! You can see the printer via AirPrint but can’t connect, right? That usually means Bonjour (mDNS) discovery works, but traffic is blocked or isolated by the firewall/router. We’ll check UDP 5353 for mDNS, TCP 631 for IPP/IPP(S), multicast/IGMP snooping, and AP/client isolation on guest Wi-Fi. What brand is the printer (HP/Epson/Canon/Brother) and are the iPhone/Mac on the same subnet/VLAN as the printer?

Customer

HP OfficeJet on Ethernet. iPhones see “AirPrint” but it won’t connect. Mac sometimes says “unable to communicate”. We use an ISP router + mesh APs. Guest network is on.

Technician

Classic. When AirPrint shows but won’t connect, the usual culprits are:
• Bonjour blocked / mDNS disabled on router — discovery packets appear but sessions fail.
• Firewall rules not allowing UDP 5353 (mDNS) and TCP 631 (IPP) between devices.
• AP/Client isolation or guest Wi-Fi prevents device-to-printer traffic.
• Mesh features (multicast filtering, IGMP snooping) not forwarding mDNS across APs/VLANs.
• iPhone and printer on different subnets/VLANs.
Quick plan: put devices on one LAN, allow UDP 5353 + TCP 631, enable Bonjour forwarding/multicast, turn AP isolation off, then try Secure AirPrint (IPPS).

Customer

How do I confirm the same subnet/VLAN?

Technician

Check same subnet/VLAN: On iPhone go to Wi-Fi → (i) and note the IP (e.g., 192.168.1.x). On the printer status page or its web panel, compare the first three octets (192.168.1). If they differ (e.g., 192.168.0.x vs 192.168.1.x), AirPrint traffic crosses subnets and many routers block mDNS there. Move both to one LAN or enable Bonjour/mDNS across VLANs on the router.

Customer

They match. What router settings should I change first?

Technician

Firewall/router quick fixes:
1) Allow UDP 5353 (mDNS) and TCP 631 (IPP) on LAN/WLAN. If there’s a toggle for Bonjour or AirPrint, turn it on.
2) Under Wi-Fi advanced, enable multicast traffic and, if present, IGMP snooping or Bonjour forwarding on the mesh so mDNS is not dropped.
3) Turn AP/client isolation off (especially on the guest SSID). Isolation makes devices invisible to printers even when AirPrint advertises.
4) Reboot printer → router → iPhone/Mac in that order and retry.

Customer

AirPrint works on iPhone but not on my MacBook. Any Mac-specific steps?

Technician

When AirPrint works on iPhone not Mac:
• Remove and re-add the printer in System Settings → Printers & Scanners. Choose Secure AirPrint (IPPS) when possible.
• If adding by URL, use ipp://printer-ip/ipp/print or ipps://printer-ip/ipp/print (HP/Epson/Canon/Brother common paths).
• If CUPS shows “unable to communicate”, macOS discovered the printer via mDNS but the connection on TCP 631 is blocked; re-check router rules and any Mac firewall profiles.
• For deep checks you can enable the CUPS web interface at http://localhost:631 and view the queue errors.

Customer

We keep a guest network for visitors. Could that break it?

Technician

Yes. Many routers put the guest SSID on a separate VLAN with client/AP isolation. AirPrint may appear but won’t connect because peer-to-peer is blocked. Keep printers and Apple devices on the main SSID, or explicitly allow mDNS (UDP 5353) and IPP (TCP 631) between the guest and printer VLANs and disable isolation.

Customer

What about mesh systems? We use three APs and a switch.

Technician

On meshes, enable Bonjour forwarding or allow multicast across APs. If your switch has IGMP snooping, keep it on but also enable mDNS reflector/querier if available so UDP 5353 reaches all APs. If your mesh has a “Block multicast/broadcast” toggle, turn it off or add an exception for mDNS.

Customer

We tried again after the rule changes. The iPhone now connects, but prints are slow.

Technician

Good sign. For stability, add the printer as Secure AirPrint (IPPS) on Mac and iOS when offered. IPPS still uses mDNS discovery but is more reliable through some firewalls. Make sure QoS or bandwidth-saving features aren’t throttling TCP 631. Avoid RAW 9100 unless your environment requires it.

Customer

If it breaks again, what’s the fastest checklist?

Technician

Rapid checklist when AirPrint won’t connect:
1) Confirm devices and printer on the same subnet/VLAN.
2) Allow UDP 5353 (mDNS) and TCP 631 (IPP/IPPS) in router and any software firewalls.
3) Disable client/AP isolation; keep off guest SSIDs or add exceptions.
4) Enable multicast/Bonjour forwarding and appropriate IGMP settings on mesh/switch.
5) Add via Secure AirPrint (IPPS) or ipp(s):// path; retry from Mac and iPhone.
6) Power-cycle printer → network → device.

Customer

Done — prints are instant now. Appreciate the help!

Technician

Summary: If AirPrint shows but won’t connect, it’s nearly always Bonjour blocked or mDNS/IPP ports filtered. Put devices on one subnet/VLAN, allow UDP 5353 and TCP 631, enable Bonjour forwarding / multicast & IGMP snooping, and make sure AP/client isolation is off. If needed, add the printer using IPPS. Need hands-on help? Open the chat.

Quick answer: the accepted fix

Accepted fix when AirPrint not connecting: keep printer and Apple devices on the same subnet/VLAN, allow UDP 5353 (mDNS) and TCP 631 (IPP/IPPS), enable Bonjour forwarding / multicast with IGMP snooping configured, and turn AP/client isolation off (guest Wi-Fi). Re-add the printer with Secure AirPrint (IPPS).

FAQ

Step-by-step (Router/Mesh)

1. Place printer and Apple devices on the same subnet/VLAN (avoid guest SSIDs).
2. Allow UDP 5353 and TCP 631 on LAN/WLAN firewalls.
3. Enable Bonjour forwarding or multicast and review IGMP snooping on mesh/switch.
4. Disable AP/client isolation on Wi-Fi.
5. On Mac/iOS, add the printer as Secure AirPrint (IPPS) and test.

Step-by-step (macOS)

1. Remove the printer in System Settings → Printers & Scanners, then Add → Secure AirPrint.
2. Alternatively use ipp:// or ipps:// with the printer’s IP and path /ipp/print.
3. If CUPS shows unable to communicate, recheck router rules for TCP 631 and Mac firewall profiles.

Sources

• Apple — About AirPrint and supported environments
• Apple — Add a printer on Mac (IPP/IPPS)
• Apple — Bonjour (mDNS) overview
• HP — AirPrint/Bonjour networking guides
• Epson — AirPrint/IPP support
• Canon — AirPrint setup
• Brother — AirPrint settings

Matt ● replies in < 1 min

Technician Expert

⭐⭐⭐⭐⭐ Trusted by 27,000+ customers

Alex · Expert's Assistant

Start Chat

5 Tech Support Specialists are online right now.