Phone won't switch to the nearest mesh node or extender?
You're standing next to the mesh node and your phone is still holding on to the router at the other end of the house. That isn't a fault: it's how phones decide when to move, and once you know the rules you can work with them.
In short
- The phone decides when to switch, not the router. Apple documents that an iPhone stays on its current access point until the signal drops below -70 dBm.
- It then moves only to a unit that's clearly stronger: at least 8 dB better while data is flowing, 12 dB when idle.
- An extender with its own network name (often ending in _EXT) is a separate network: phones won't move to it on their own at all.
- What helps: one network name everywhere, a mesh system with fast roaming (802.11k/v/r) turned on, and nodes placed so their coverage overlaps where you walk.
On this page
It's one of the most common frustrations with mesh systems and extenders. You walk into the room with the new node, the one you bought precisely for this room, and your phone carries on using the router at the other end of the house, with two bars and a call that keeps breaking up. Turn the Wi-Fi off and on and it jumps to the right unit immediately.
Nothing is broken. In Wi-Fi, the device chooses which access point to use, and phones are deliberately reluctant to switch.
How a phone decides when to move
Apple publishes the rules its devices follow, in its documentation for network administrators. An iPhone or iPad keeps its current access point until the signal from it drops below -70 dBm. A Mac waits until -75 dBm. Above that level, the device doesn't even look for something better.
Once it crosses the threshold, it scans for other access points with the same network name and moves only if one is clearly stronger: at least 8 dB better for an iPhone that's actively sending data, 12 dB better when it's idle, and 12 dB for a Mac. In Apple's own example, an iPhone whose connection has dropped to -75 dBm during a call looks for an access point of at least -67 dBm.
Android phones and laptops use their own rules, but the principle is the same everywhere: switching costs a brief interruption, so devices only do it when staying is clearly worse.
This explains the frustrating situations. In the room next to the node, the far router may still reach you at -66 dBm. That's above -70, so your iPhone doesn't move, even though the node beside you would give you -45. You're connected, just not as well as you could be.
First check: one network or two?
Many plug-in extenders create a second network with a name like MyHome_EXT. To a phone, that's a different network, not another access point of the same one. Phones don't roam between different networks automatically; they stay on the one they joined until it's lost completely, and then pick whichever they remember.
If you see two names, give the extender the same name and password as the router, if it allows it, or replace it with a mesh system, where all units share one network by design. This one change fixes a lot of "won't switch" complaints.
See which unit your phone is actually using
An iPhone doesn't show which access point it's connected to. The mesh or router app usually does: open the list of connected devices and look for your phone. Most apps show the unit it's on and often the signal.
AirPort Utility's Wi-Fi scanner on iPhone helps from the other side: it lists each unit of your network separately with its signal, so you can see how strong the near and far units are where you stand. How to check Wi-Fi signal strength on iPhone explains how to turn it on.
What actually helps
Turn on fast roaming. Mesh systems and better routers support three standards that make switching quicker and better informed: 802.11k tells devices which access points are nearby, 802.11v lets the network suggest a better one, and 802.11r makes the handover itself faster. Apple devices support all three. Look for a setting called fast roaming, seamless roaming or 802.11r in your mesh app; some systems have it on by default. If a very old device stops connecting after you enable it, that device is the reason it's sometimes off.
Place the nodes so their coverage overlaps where you walk. Switching works when, at the point where the far unit drops below -70 dBm, the near one is already clearly stronger. If the nodes are too far apart, there's a stretch of corridor where neither is good, and that's where calls drop. Professional designs for calls aim for about -67 dBm from two access points at every point. At home, check the path you actually walk with a phone in your hand; where to put a mesh node explains how.
Use the roaming assistance setting, carefully. Some routers can nudge or disconnect a device whose signal falls below a chosen level, so it reconnects to a closer unit. It works, but set the threshold too high and devices get kicked off in normal use. Treat it as a last adjustment, not a first fix.
For a device that never moves, stop worrying about roaming. A smart TV or a printer stays where it is; if it's on the wrong unit, a restart usually makes it pick the nearest one, and many mesh apps let you assign a fixed device to a unit.
What doesn't help
Turning Wi-Fi off and on works every time, but only until you move again. And making the far unit weaker so the phone gives up on it sooner, by lowering transmit power, can help in a carefully planned office but usually just creates new weak spots at home.