When did you become a grownup? For me, I think, the big leap to responsibility happened when I began paying my own phone bill. In college this was a big taste of adulthood. If your name was on the phone bill, it was up to you to make your roommate pay her share. If you didn't fall behind, you could use the phone company as a credit reference when you got your own place.

Having negotiated this hurdle successfully, I moved on to my own room, then my own apartment, then my own house. The phone bill was just something that happened every month. It became a defining issue in my last romantic breakup, when I realized I was paying the phone bills of a guy who wouldn't even go to the movies with me.

But the bill itself hasn't changed much. Oh, they redesigned it from time to time, and things got a little fragmented in the AT&T breakup, but essentially it arrived, I looked at the figure on the front and wrote a check. That was it.

Last month, they told me they wanted to change it. Instead of one bill, I would now get two, one for my regional service and one for long-distance.

Why, I wondered, must I spend twice as much time dealing with my phone service as I did before? Why must I write twice as many checks, use twice as many stamps, recycle twice as many bills? I access both services the same way, by picking up the phone and dialing. Surely if they can cooperate to that extent, they can continue billing me on the same piece of paper?

Like most Americans, I am used to a convenience economy. I pull up to the parking place closest to the door, or use the drive-through, even though I need the exercise of a walk across the parking lot. Yet like many, I do not mind giving up convenience in a good cause. I spend extra time gathering, separating and transporting material to be recycled, because I want to believe it will somehow help a small part of the planet to do so.

Paying two phone bills, though, smacks of bureaucratic interference for no good reason. The mailing announcing this change trumpeted it as some kind of great new advance in phone-bill technology. I called the customer service line, and the unfortunate person on the other end parroted a list of advantages of her company's service before finally listening long enough to admit that yes, she could keep my service on a single bill and would make my wishes known to her computer.

Along with convenience, we're used to choices. We celebrate our freedom to choose when we vote in an election, follow a religion - or select a long-distance company. Early in life, I learned the power of economic choices when my mom chose to buy products made by companies that were my father's customers. By supporting them, we supported my dad. Now, I use the power of my pocketbook to support companies that share my goals or treat me well.

So I'll be making a new choice of phone service. In the meantime, my long-distance friends are getting e-mail.