Number Portability arrives in the 100 largest U.S. markets, though public interest so far has been luke-warm. Meanwhile there's little accountability surrounding how much is being charged for the honor.

The majority of the nation's retailers claim they didn't notice an increase in business this week as local number portability (the ability to transfer your mobile number between services) went live. Analysts predicted tens of millions of migrations during the initial several months of the LNP push, but according to Wireless data farm Mobile Competency, fewer than 100,000 people attempted number migration on Monday, with a 40% failure rate among those tried.

There were several concerns leading up to the launch. Bells (those without wireless divisions, anyway) logically complained there should be reverse number portability from cell to home phone. Many carriers argued that they weren't ready. Environmentalists, almost un-noticed underneath the dull roar of profit and convenience chatter, argued that the idea would likely result in land-fills brimming with cell-phones users could no longer use.

More interesting though is the methodology used to determine the hikes customers would see on their monthly bills. Data suggests that carriers have taken the opportunity as an excuse to pad their coffers, with the FCC really paying little attention.

While it took years for the rules to arrive, consumers have actually been paying for the number portability switch for some time. According to a recent study by the Center for Public Integrity, users in the U.S. have shelled out $629 million in related fees since January of 2002.

It's a complicated process and certainly shouldn't be without cost, but what's interesting is how these fees are being calculated.

Carriers performed their own in-house estimates as to how much the service would cost to implement. These estimates are not required to be made public, and according to the CPI, the FCC has absolutely no system in place to confirm the calculations are even accurate.

The estimates vary significantly across the board, with smaller carriers often projecting higher costs, despite the majority of carriers using the same software and hardware to complete the upgrades. Estimates show that companies like Nextel will likely have collected some $283 million in fees before they provided a single user with the service. Nextel's own numbers indicate the deployment of LNP will only cost the company $100 million.

Speaking to the CPI, Consumer's Union attorney Chris Murray says there is "zero accountability," adding that "There's no way for consumers to know. Forget about trusting the carriers to be honest in their accounting for what these line items cost, we don't even get [an accounting] — consumers have no information whatsoever about what the costs of these mandates are."

The remainder of the $629 million in fees are for number pooling, enhanced 911 and digital wiretap requirements (providers charge fees to cover the cost of adhering to the Communications Assistance for Law Enforcement Act, which forces carriers to have their networks "wiretap ready").

Verizon Wireless was one of the only carriers not to charge LNP fees pre-launch (they've been charging for number pooling only). According to Verizon Wireless, they've estimated the cost of implementing local number portability to be around $60 million - one of the lowest estimates among providers.

This week the company announced they'd be tacking on a 40 cent per month fee for all of its 36 million wireless subscribers. That brings the total in costs and fees to $173 million a year for Verizon Wireless subscribers (not including any new customers that will be signing up for a service), when their own estimates indicate LNP should cost $60 million to implement.

At the moment, T-mobile is the only major carrier not charging a monthly fee for the service. The fees for the service from most providers range from five cents to $1.75 per month.