I was reviewing opt-outs per SMS send with a client and noticed a big spike in the rate. There was nothing about the message, offer, cadence or proximity to a holiday ? factors previously identified as culprits ? that would have led to the result.  

Then the client realized the cause. This message was for a limited-time offer, and it wanted to make sure customers received the message well in advance.  

?We sent it kind of early.?   

?How early??

?8 a.m. Central.?

Oy, that is 6 a.m. on the West Coast. You can imagine how excited a customer is to be awakened at 6 a.m. with a marketing message, even if it is the best offer imaginable. 

We decided to speed up our project to merge the SMS numbers with the credit card and loyalty program to determine the time zone for the customer. 

Lacking a match, we would send during the safe-to-send window ? no earlier than 10 a.m. on the West Coast and no later than 9 p.m. on the East Coast.

Then I had a second experience that made me doubt this approach. 

My wireless carrier certainly knows my time zone, but may not know my current location. Yes, geo-location can pinpoint some users? locations, but certainly not all.

Based on these examples, let us agree to these best-practice tips:

1. Unless you are 100 percent certain of the user?s time zone, based on current location, do not send outside of the 10 a.m. West Coast through 9 p.m. East Coast window. You can send silent push, however. 

2. Monitor sends to make sure technical or infrastructure issues do not result in a delay in sending your entire file. If you exceed the safe window, cancel the job and resume the following day.

3. Have an apology ready. Wait until the safe window and apologize. Include an exceptional offer, if applicable, to show you mean it. No, you cannot send to those who have already opted out. You can only acknowledge receipt and state that the customer will no longer receive messages from you. 

4. Monitor your opt-outs. Attribute all SMS opt-outs to the previous message, up to the date a new one is sent. The folks at Clever Tap tell me they can do this for app uninstalls as well. Then chart against your message content and identify the factors that may have contributed to a spike or high-water mark in the rate.

REMEMBER: When a customer is awakened at 4 a.m., she is not angry with your push or SMS program. She is angry at your brand. Do not squander brand love: pay attention to send time.