How Many Messages Per Month Should I Send?
This will vary depending on what type of business or organization you're working with and the type of clientele that you'll be messaging. In most cases, it's best to not go over 4 messages per month. Any more could start to annoy your subscribers and cause them to opt-out.
As a rule of thumb, think about how many times you'd want to receive text offers from your favorite business or organization in a similar type of industry. Remember, quality over quantity is key. Every campaign you send should create true value for the customer.
Another factor to keep in mind here would be 1-time texts to subscribers. For example, the birthday text only sends out to a subscriber once per year. In that given month, they may have received 1 birthday text, plus your normal 4 messages. In this case, that user would receive 5 messages in that given month. For reasons like this, consider your busiest month as the month to base your frequency on.