There are several voice-over-internet-protocol (VoIP) services available, but many of them come at a high cost per user, per month. For small businesses with a larger staff, the cost may be too high to consider. Enable your team to connect with clients and leads with free VoIP phone services.
The apps work on most smartphones, and some include desktop or browser versions. The free plans won’t set you back a cent if you keep calls and texts to domestic lines only (U.S. and Canada). Many VoIP services for phones use ads to keep the apps free to use but usually offer a way for you to pay to remove ads or add-ons to make the app more useful (such as for international calls or voicemail).
There aren’t many free VoIP phone service providers out there catering to smartphone users, so we included a couple of video call options that also have free plans. These services are ideal for freelancers, startups and small businesses on tight budgets. As your company grows, you can upgrade to more robust plans with the best VoIP phone features.
sumber: https://www.forbes.com/advisor/business/services/best-free-voip-services/