The short answer to how to change NAT type on PC is to identify the game's actual connection path before changing settings. Check the game or platform diagnosis, your PC's service and firewall, then the home router and ISP boundary. The five methods below apply to different causes; UPnP, bridge mode and a public address are not interchangeable fixes.［1］［2］［4］［5］

Key Takeaways

NAT is a router mechanism that lets multiple private devices share one public IPv4 address. It is not a single Windows toggle.［1］

If your ISP gateway and your own router are both routing, you may have double NAT, which can break gaming and port forwarding.［2］

If your ISP uses CGNAT, changing settings on your home router may never produce a truly open NAT.［2］［5］

UPnP is convenient but opens ports automatically. Manual port forwarding is more controlled but more work.［3］［4］

Broad DMZ exposure is not a general fix or a temporary diagnostic step. Keep the firewall and use only necessary rules.［4］

What Is NAT Type, and Why Does It Affect PC Multiplayer?

NAT stands for Network Address Translation. A home router maps multiple devices on your local network to one public IPv4 address for external communication. RFC 3022 defines this traditional NAT/NAPT model. Mapping and traffic filtering are separate behaviors; application access still needs authentication and firewall policy.［1］

Open, Moderate and Strict summarize a particular platform’s connectivity test. Limited inbound reachability can affect peer-to-peer sessions, but these labels do not establish the cause of a failed lobby or predict every game’s behavior.

For more background, read What Is a VPN? A Complete Beginner’s Guide and What Is VPN Port Forwarding? How It Works and Why It Can Be Risky.

First Check Whether You Can Change It at All

This is the most important step. A failed lobby join can involve the game server, account permissions or a local firewall as well as NAT. Record the game, platform, Windows version and router model/firmware. Do not change an employer's or shared network without its administrator's permission.

Check your current NAT type on PC

Use the current game's or platform's documented network diagnostic and record its result. Windows does not offer a universal NAT-type switch; a legacy Xbox networking menu is not a reliable path for every Windows version.
Record the actual failed task: joining a room, hosting, invitations or voice chat. If no NAT label is available, treat these as symptoms, not proof of Strict NAT.
Check the game's service status and account eligibility before changing the network. A working browser does not prove its peer-to-peer path works, and an Open label does not prove all games work.

Compare the same game/task before and after one change. Open, Moderate and Strict are platform-specific labels, not guarantees for other platforms.

1. Check for double NAT

Double NAT can occur when an ISP gateway and a second home router both route. NETGEAR notes that it can complicate gaming and port forwarding, although it does not affect every application.［2］ Read the status of devices you own before deciding which layer is responsible.

Read your router's WAN IPv4, not the PC's LAN address.
On the same connection, use the site's IP tool and compare the visible IPv4. An IPv6 result cannot be compared with a WAN IPv4.
Account for a VPN or proxy on that request. If an optional tunnel can be stopped with permission, compare without it; otherwise record the limitation instead of treating the tunnel's exit as your ISP address.
Draw the upstream devices and read their WAN status where permitted. A mismatch suggests another translation or egress path but does not identify its owner by itself.

RFC1918 private ranges are 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. The separate Shared Address Space 100.64.0.0/10 runs from 100.64.0.0 to 100.127.255.255; not every 100.x address belongs to it. None of these WAN clues alone proves ISP CGNAT.［6］ A private upstream router you control calls for a different remedy from an ISP-managed boundary.

2. Check for ISP CGNAT

CGNAT allows an ISP to share public IPv4 addresses among subscribers. A correct home-router mapping cannot configure an arbitrary upstream ISP mapping. Confirm the topology and supported inbound options with the ISP.［5］ Address sharing is not proof that every game requires a public address: a game may use outbound sessions or a relay.

Bridge mode removes a routing/NAT layer in a gateway you are allowed to manage; it does not remove ISP CGNAT. If the ISP confirms that boundary, consider a supported public IPv4 or provider mapping, or an application-compatible IPv6/relay route. Keep authentication and firewall policy whatever path you choose.

How to Change NAT Type on PC With 5 Fixes That Actually Help

Choose one diagnosis-led method. The author compiled this guide from official documentation without complete end-to-end testing. Check listeners/firewall, back up settings, change one item, retest and revert ineffective changes.

Method 1: Assess UPnP on your router

Consider UPnP only where your router and game document it, on a trusted home LAN you administer. Untrusted local applications can also request mappings; UPnP cannot configure arbitrary ISP CGNAT mappings.［3］

Read the instructions for your exact router and firmware and record the original UPnP setting and mappings.
If this is an approved choice, enable it, save, and start the game that requests the mapping. Restart only if that device's documentation requires it.
Inspect mappings if the router shows them; retest the game's status and original failed task.
Without improvement, stop the game's automatic mapping requests, restore prior settings, remove only experiment-created mappings using supported controls, confirm they stay absent and perform the fresh-connection check below.

Applications may recreate mappings while automatic mapping stays enabled; NAT state may preserve old sessions.［7］［8］ Close the test session; test a new authorized external connection with the same service, address family and protocol. The withdrawn path should reject it.

Use documented manual rules for port/source control; Strict alone does not justify UPnP.

Method 2: Turn double NAT into single NAT

Only change the home-controlled layer identified in the diagram. You can keep the ISP gateway routing and put a supported second router in AP mode, or use supported ISP gateway bridge mode with your own router managing the connection. These choices change different management and Wi-Fi responsibilities.［2］

Back up both configurations and confirm the exact model instructions, current management addresses and a local recovery path.
Before bridging an ISP gateway, obtain required access credentials and VLAN settings, and confirm IPTV/voice and remote-management implications with the ISP. Stop if the requirements or restoration procedure are unknown.
Make one supported mode change, reconnect through the documented management address and check ordinary internet access and WAN status.
Retest the same game. If access or required ISP services fail, restore the previous mode/configuration through the recovery path; do not use factory reset as the default rollback.

Check the remaining boundary: one fewer home NAT layer does not establish inbound access.

Method 3: Ask your ISP about a public IP

For confirmed CGNAT, ask about the path your service actually needs.［5］

Is a reachable public IPv4 or a supported inbound mapping available, and are the required protocol and ports allowed?
Is the address dynamic or static, and what fees, contract terms or service changes apply? Static does not necessarily mean publicly reachable.
Is native IPv6 supported by the ISP, game and both endpoints, or does the application offer an authorized relay instead?

Do not buy an address just to obtain an Open label. After an agreed ISP change, read the actual WAN status, repeat the same task and verify only the intended service. Keep host filtering; IPv6 also needs an appropriate inbound rule. If the option does not fit, ask the ISP to restore the previous service and review local mappings left behind.

Method 4: Configure manual port forwarding

Use the game's documented ports only when it needs inbound traffic and the public boundary can deliver it.

Confirm the service is running and listening on the intended interface: loopback-only listeners cannot accept forwarded traffic. Verify TCP/UDP requirements.
Reserve the PC's LAN address through supported DHCP reservation, or use a documented static configuration that avoids conflicts.
Map only the required external/internal ports and protocol to that address. Restrict sources where supported and practical for the game's peer model.
Keep application authentication and the firewall. From an authorized external connection, test the actual task; if source restrictions are configured, also verify that an excluded source is denied. A LAN test against the public address may depend on NAT loopback.
When ineffective or finished, stop automatic mapping requests; remove only task-added mappings/firewall exceptions and perform the fresh-connection check above. Do not expand ports for unknown failures.

Troubleshoot in order: listener/binding, local rule, home mapping, upstream boundary, then the platform. TCP and UDP need different tests; no UDP reply is not conclusive evidence of a blocked port. If name resolution itself fails, consult device DNS settings rather than claiming DNS changes open NAT.

Method 5: Check Windows network type and firewall exceptions

Windows Firewall can block an otherwise reachable application. Microsoft recommends allowing only known applications or necessary ports and withdrawing unused exceptions.［4］ Do not turn it off or mark an untrusted network Private just to get a favorable NAT label.

On Windows 10/11, open Windows Security → Firewall & network protection. Read the active profile and existing application allowance; administrator permission may be required to change it.
For a trusted game that needs it, use an application-scoped allowance on the appropriate profile. If a specific inbound rule is needed, constrain its application, protocol, port and source as the design allows.
Retest the same task without changing the router at the same time. A reachable port does not authorize an application account or repair a matchmaking outage.
If the exception did not help or access is no longer needed, remove the application allowance or disable the rule you added, and check the original protection is restored.

For tunnel, adapter or security-software conflicts, use VPN diagnosis and vendor instructions; retain protections.

Why I Do Not Recommend Opening DMZ First

A consumer router's DMZ-host setting can forward broad unsolicited inbound traffic to one host, subject to the router's implementation. It is not a substitute for the exact service rule and does not remove ISP CGNAT. Do not use it as a general fix or a temporary diagnostic step.

Keep the firewall active and check the documented service with the smallest necessary allowance.［4］ If an earlier experiment already enabled DMZ, restore the prior setting and review any associated mappings. Verify the intended service's exposure again after the change; do not assume a better NAT label establishes safe access.

Can a VPN Change NAT Type to Open?

Usually no. Your router and ISP control home NAT. A VPN may change included traffic’s outbound route and encryption; that does not automatically create a public inbound path.

VPNs are better for different problems:

Situation	Can a VPN help?	Notes
ISP CGNAT	Usually not directly	The root cause is the ISP boundary
Unsafe public Wi-Fi	Yes	It encrypts outbound traffic
Poor cross-region routing	Sometimes	Depends on VPN server routing quality
Reducing unnecessary port exposure	Indirectly yes	You do not need to open inbound ports for everything

To check whether your VPN itself is working, read VPN connection and exit-IP checks.

Summary

To change NAT type on PC, identify the actual game/platform path and administrator first.
Distinguish home double NAT from the ISP's CGNAT boundary.［2］［5］
Choose the applicable method, change one setting, verify the original task and restore ineffective changes.
Use narrow mappings and firewall allowances; DMZ or disabling protection is not a general remedy.［4］

FAQ

What is the fastest way to change NAT type on PC?

There is no universal fastest fix. First confirm the game diagnosis, listener and topology. On a trusted home LAN, documented UPnP may help, but it should be a reversible choice, not an automatic first step or a reason to restart every device.［3］

Why is NAT still strict after port forwarding?

The most common reasons are: you configured the wrong router, your PC does not have a fixed local IP address, or your ISP uses CGNAT and the real public boundary is outside your home.［2］［5］

Does double NAT always affect gaming?

Not every game fails immediately, but double NAT can make lobbies, voice chat, port mapping, and device-to-device communication less reliable. NETGEAR specifically mentions online gaming and port forwarding as affected areas.［2］

Are CGNAT and double NAT the same thing?

No. Double NAT means two layers of translation. CGNAT means the ISP is also doing NAT and multiple subscribers share public IPv4 addresses. In real networks, both can appear together.［2］［5］

Is DMZ better than port forwarding?

No. Broad DMZ-host exposure does not establish which protocol, listener or upstream boundary failed. Use a documented narrow rule and keep the firewall; do not use DMZ as a general or temporary test.［4］

Can a VPN directly turn strict NAT into open NAT?

Usually no. A VPN is an encrypted outbound path. It does not automatically give you a public IPv4 address or remove your ISP’s CGNAT.

What NAT type will a game show while a VPN is connected?

The label reflects the path that the game actually uses. Traffic routed through the VPN may encounter its NAT/filtering, while excluded traffic can still use the home path. A dedicated IP alone does not establish inbound support: an explicit mapping/service, a listener and firewall permission are still needed. Compare only with administrator permission to stop an optional VPN; otherwise record the routing limitation.

Disclaimer This article provides general home networking and PC multiplayer troubleshooting guidance. It does not guarantee ISP service behavior, router compatibility, or game connectivity. Before changing bridge mode, public IP settings, or open ports, confirm your device model and broadband plan limits. AethoVPN may change the route seen by a game, but it cannot alter the home router's NAT mappings, ISP address assignment, or matchmaking policy.

Sources

Sources checked 9 October 2026

Related Articles:

How to Change NAT Type on PC