SK Telecom APN settings for Korea LTE and 5G

Before changing the APN

Use this page when a SK Telecom SIM is active but mobile data does not browse, apps stay offline, hotspot sharing fails, or the phone lost its profile after a network reset. The first rule is to make the smallest useful change. An APN profile controls how the phone reaches the packet data gateway, but many fields are filled by the SIM, the operating system, or the carrier profile already stored on the device. Editing every field at once can make a simple problem harder to diagnose.

For South Korea, start with a readable profile name and the APN value shown above: `lte.sktelecom.com`. For SKT travel SIMs, automatic profile installation can be safer than manual APN editing when iOS locks the menu.

Android setup path

On Android, open Settings, Network and Internet, SIMs, Access Point Names. Samsung and other vendors may call the same area Connections, Mobile networks, Access Point Names. If an existing SK Telecom profile is already selected, compare it before adding a duplicate. If the existing profile is blank, broken or clearly from another carrier, add a new APN. Fill Name with `SKT LTE Internet`, APN with `lte.sktelecom.com`, and APN type with `default,supl` only if the phone shows that field.

If the phone has two SIM slots, confirm that the SK Telecom SIM is selected as the data SIM. Many failed APN edits are actually dual-SIM selection problems. After saving, test with WiFi disabled, because WiFi can make a mobile data problem look fixed when it is not. Open a lightweight web page first, then test messaging, maps, app store access and hotspot sharing if those features matter to you.

iPhone and iPad setup path

On iPhone, first check for a carrier settings update by opening Settings, General, About and waiting a few seconds. If an update prompt appears, install it before typing a manual APN. If the Cellular Data Network screen is available, enter `lte.sktelecom.com` in Cellular Data APN and keep username and password exactly as shown in the table or blank when your plan does not require them.

If iPhone hides the APN menu, do not keep searching random profile websites. That usually means the carrier bundle controls the values. In that situation, reseat the SIM, restart the phone, reset network settings only if you can rejoin saved WiFi networks, and ask the carrier to refresh data provisioning if the line still attaches to voice but not data.

How to test the result

After saving, toggle airplane mode for ten seconds, disable WiFi and open a browser. If the page loads, run a second test in an app that previously failed. If only some apps fail, the APN may be correct and the issue may be app cache, private DNS, VPN, content filtering, low storage or a regional service block. If nothing loads, check signal strength, data balance, data roaming status, preferred network mode and whether the phone is locked to a network band that is weak in your area.

Do not judge the APN by speed alone. A correct APN can still be slow when the tower is congested, the plan is throttled, indoor signal is weak, or the phone is attached to an older radio layer. First prove that data can connect. Then evaluate speed near a window, outdoors and at a different time of day before assuming the profile is wrong.

Common mistakes to avoid

The most common mistake is deleting every old profile and losing a carrier-provided configuration that only needed to be selected. The second is copying MMS values into the internet profile. MMS fields are separate and should only be edited when picture messages are the issue. The third is changing MCC and MNC values by hand. Those values identify the network, and a wrong pair can stop the phone from saving or selecting the APN.

Another common mistake is testing while WiFi is still connected. Turn WiFi off during the test. If your phone uses VPN, private DNS, parental controls, ad blockers or corporate device management, pause those features for one test. They can block browsing even when the SK Telecom APN is correct.

When roaming changes the answer

If you are outside South Korea, the same APN may still be accepted, but roaming must be enabled and your plan must allow roaming data. Some carriers use the home APN for roaming; others push a profile automatically. If the SIM registers on a visited network but data fails, check roaming permission, spend cap, unpaid balance and whether LTE or 5G roaming is available for that partner network.

For travel, keep one simple note before editing: the original APN name, APN value and whether the old profile was selected. That makes it easier to go back if the new profile does not work. If the phone accepts eSIM profiles, also confirm that the physical SIM and eSIM are not competing for the data line.

Final check

This route is preserved because people still reach the site through carrier and country-specific APN searches. The content here is written as a practical setup checklist: enter the minimum APN value, test in a controlled way, and only then move to deeper troubleshooting. If mobile data still fails after the APN, the next most useful checks are SIM provisioning, plan status, preferred network mode and signal quality in the exact location where you are testing.