Absolutely not!

While adding numbers manually is legal, you must have the users clear and written consent. Numbers collected over the phone, website or a 'fishbowl' must clearly state what they are signing up for.  

CTIA guidelines require the following for recurring marketing messages: (see section A.2.03 for more detail)

Users Must Opt-In

Manual or automated addition of numbers is allowed only if you have gained express consumer consent.  

Example opt-in methods:

• Send a message containing a keyword (EG. JOIN, PROMO, SPECIALS, etc.)
• Sign up at a point-of-sale (POS) location where clear express consent is provided
• Opt in over the phone using interactive voice response (IVR) technology

Following CTIA and Carrier guidelines your campaign must send a single opt-in confirmation message after the addition of the users number to your list.

Voxox respects CTIA guidelines as well as those put forth by carriers.  Your messages are subject to our compliance teams approval 

References 

* https://usshortcodedirectory.com/ctia-short-code-monitoring-handbook/   (A.2.03 OPT-IN)