Generally, no—unless the code is specifically a "credit" code. Most third-party codes are for new subscriptions only . However, some codes work as "account credit." Read the fine print of your voucher.
While the free version is excellent, activating a Plus plan offers several key advantages: Access to 10 Gbps servers. Global Coverage: Servers in over 90 countries. NetShield: Built-in ad, tracker, and malware filtering. proton vpn activation code
A significant portion of web searches for "Proton VPN activation code" lead to malicious sites. Common threats include: Generally, no—unless the code is specifically a "credit"