When a customer is talking on the phone and arrives at the front of a line to be served, she should end her phone call immediately. If she doesn’t do that, say this:
“Ms. Customer, other customers are waiting to be helped. Rather than make them wait while you finish your phone call, I’ll be happy to take care of your request as soon as you’re done.” Give her the opportunity to end the call, and if she doesn’t, smile and courteously say to the next person in line, “May I help you?”
Source: Renee Evenson, author of Powerful Phrases for Effective Customer Service
