One service I've found so far which might fit the bill is tollfreeforwarding.com, as it seems like their pricing ($5/mo. & 5.7c/minute) is very reasonable. The only concern I have here is how unanswered calls are charged. If the number they assign me is already known and gets tons of spam calls, will I be charged for calls I don't pick up? Source: about 2 years ago

Get a number on https://tollfreeforwarding.com and configure IVR rules there. Source: over 2 years ago

I use Hushed app. It gives me a phone number that I can use for WhatsApp and to receive SMS confirmation codes from various archaic services that still validate you thorough the insecure SMS. https://hushed.com/. - Source: Hacker News / 6 months ago

Have you tried a burner app (like https://hushed.com)? If you shop around you can find good deals, like a lifetime # on the cheap). Source: about 1 year ago

Hushed.com works in Canada, not free but not that expensive either. Source: over 1 year ago

Hushed (while privacy-focused) allows for multiple numbers across multiple devices, and has been around for a while. Source: over 1 year ago

In addition to all the standard features of any other cell phone (e.g., caller ID, call forwarding), the Hushed Lifetime Number subscription also includes some great additional features such as custom voicemail greetings, text message alerts when someone has left you a voicemail, international calling rates that are among some of the lowest in the industry, and more! Plus, because it works over Wi-Fi or cellular... Source: over 1 year ago