Use IP whitelisting when your provider supports it and your public source IP stays stable, especially if your app cannot send proxy credentials. Choose username and password when you move between networks; use separate sub-users where the provider offers them.
Authentication controls proxy access, not whether websites see a rotating or sticky residential IP.
27Proxy is an independent reseller of residential proxy activation codes, including 9Proxy, Thordata, 711Proxy and NovProxy. Shifter appears below as a comparison outside our range. Authentication is configured with the provider.
How does proxy authentication work?
IP whitelisting, also called an IP allowlist, authorizes the public address that connects to the proxy gateway. Add that source address to the provider's list, then use the matching endpoint without entering credentials where that mode is supported.
Your home router's private address is not the address to add. Neither is the residential exit IP that a website sees after you connect through the proxy.
Username/password authentication sends proxy credentials from your app. These may belong to a provider sub-user. They are separate from your 27Proxy login and activation code.
IP whitelisting vs username and password
| Decision | IP whitelisting | Username and password |
|---|---|---|
| Security boundary | Trusts a source address; a shared network weakens separation | Trusts a secret; leaked credentials can be reused |
| Dynamic home IP | Update the entry when the public address changes | Address changes alone do not invalidate credentials |
| App support | Useful when the app accepts host and port but cannot send credentials | Requires the app to support the provider's authentication method |
| Several devices | Devices sharing one public IP share that source identity | Separate sub-users can separate access where offered |
| Travel or mobile data | New source networks may need new entries | Usually easier across changing networks |
| Transport protection | Does not itself encrypt traffic | Does not itself encrypt traffic |
Whitelisting suits a server with a fixed outbound IP; credentials suit a laptop changing networks. Host-and-port settings still require a compatible proxy protocol and app.
Which providers support IP whitelisting?
The providers state these options and dashboard paths:
| Provider and product | Whitelist workflow | Documented detail |
|---|---|---|
| 9Proxy GB documentation | Residential Proxies Traffic → Whitelist | Up to 50 addresses; IPv4 only |
| Thordata residential documentation | Proxies → Residential Proxies → Proxy Setup → Whitelist | Batch Add manages source addresses |
| 711Proxy documentation | Whitelist in the dashboard sidebar | IPv4 only; used for API access |
| NovProxy Dynamic Traffic documentation | Dynamic Traffic - API Mode | Whitelist List manages authorized addresses |
Whitelisting is not available on every gateway. Shifter's authentication documentation states that its current Residential Proxies product uses credentials only; its legacy port-list plans use source-IP authentication.
How to whitelist your IP
This 9Proxy GB example applies to 9Proxy Residential Traffic codes, not its desktop-app IP product. Other residential GB providers use different menus.
Step 1
Find the public source address
On the network that will run the proxy, disconnect any VPN or existing proxy as 9Proxy instructs. Read the public IPv4 address from its current-IP display or a public-IP checker. Checking through a proxy shows its exit instead. For a remote server, use its outbound public address, not your laptop's.
Step 2
Add the address
Following 9Proxy's instructions, open Residential Proxies Traffic → Whitelist. Use Add to Whitelist for the displayed current IP. For another source, enter its outbound public IPv4 address in Add to Whitelist, press Enter, then click Add IP. Save only a source address you control.
Step 3
Generate the matching endpoint
Open Residential Proxies by GB → Get Proxy and select Whitelist IPs. Choose the location and session settings, enter the endpoint quantity, click Generate and copy the resulting host and port into your app.
Step 4
Check the connection
Make a request through the app and check its exit address to verify proxy use. Remove entries for networks you stop using.
How to set a proxy username and password
Step 5
Create proxy credentials
Follow 9Proxy's User-Pass instructions: select User-Pass Auth in the generator, then choose an existing sub-user or create one through Add new user. Enter its username and password, choose the bandwidth allocation type and save it with Add Sub-User.
Step 6
Enter all connection fields
Choose the location and session settings in the generator, then copy the displayed host, port, username and password exactly into the app's corresponding fields and check the connection. Keep credentials out of shared screenshots and logs.
Why does a whitelisted proxy stop working?
- Dynamic home IP: the ISP assigns a different public address. Update the whitelist to match the new source.
- Mobile data: switching from Wi-Fi changes the network path; reconnecting can change the address again.
- CGNAT: the carrier shares a public IPv4 address among subscribers. The allowlist cannot identify your device separately from others using that source.
- VPN or remote server: the gateway sees that connection's outbound address rather than the home address you saved.
If access stops, compare the current source address with the saved entry before regenerating endpoints. For authentication prompts or HTTP 407 responses, follow the proxy authentication troubleshooting guide.
FAQ
Is IP whitelisting safer?
Neither is safer in every setup. An allowlist removes the need to store a proxy password in the app, but users sharing its public source IP share that identity. Separate sub-users offer individual access where supported; their credentials still need protection.
Why did my whitelisted proxy stop working?
Your public source IP may have changed. If it still matches the saved entry, check whether that entry is enabled, the endpoint is correct and provider traffic remains available.
Can I whitelist a mobile IP?
Yes, where the provider accepts that public address. Mobile addresses can change or be shared through CGNAT, making credentials easier to maintain when the app supports them.
Does whitelisting give me a static proxy IP?
No, whitelisting only authorizes the connecting source address. Check the rotating or sticky session settings separately to control the proxy exit IP.
Can I use both methods together?
Only if the provider offers a mode requiring both. Two available authentication choices do not mean both checks apply to the same connection.