Yes, Textline does allow companies to use multiple phone numbers for different Departments or locations. Your current pricing plan will determine how many Departments you can add to your account, and you can always purchase additional Departments à la carte if you need them.
To add additional Departments, click Settings > Organization Settings > Departments, then click the blue New Department button. You can get a new number through us, use your existing Twilio number, integrate your business's Facebook messages, or text-enable / have us host SMS for an existing business landline or VoIP number.
Watch the tutorial video on Adding Departments here.