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Shopping for airfares: What you see is now what you pay

Score one for truth in advertising.

Travelers shopping for air travel no longer have to click through multiple web pages — or read the fine print in newspaper ads — to find out what their plane tickets truly cost. Instead, the first price posted must include all taxes and mandatory fees. 

“We believe consumers need to be able to see the entire price they will have to pay the first time an airfare is presented to them,” said Bill Mosley, spokesman for the Department of Transportation.

Such full-fare advertising “is a welcome change,” said Charlie Leocha, director of the Consumer Travel Alliance. “It’s important that consumers at least know the full cost of their trip while they’re looking for it.”

The rule is part of a larger package of passenger protections rolled out by the Department of Transportation (DOT), but the advertising regulation will have the most impact on the greatest number of travelers.

Consider: Last week, an online search at Southwest.com revealed one-way fares between Dallas and Chicago for $84.65, or $169.30 roundtrip. Click on those fares, though, and the actual cost with taxes and fees rises to $218.20.

Even more eye-opening, travelers searching for flights between Fort Lauderdale, Fla., and Las Vegas on Spirit Airlines might be enticed by web fares of $71 each way, or $142 roundtrip. The actual cost? $219.18, which includes $77.18 in taxes and fees.

As of Thursday, the first posted fares for the above itineraries will have to be displayed as $218.20 and $219.18, respectively.

The rule has not been well-received by the airlines. Allegiant, Spirit and Southwest are currently contesting the requirement in court, claiming that requiring airlines to post tax-inclusive fares runs counter to the way most other products and services are sold.

Related: Fight over full-fare rules takes bizarre turn

“There is no justification for treating air travel differently from just about everything else that consumers purchase, i.e., they pay for the price of goods and services and then pay tax,” said Southwest spokesman Chris Mainz via e-mail.  “Forcing airlines to include taxes will also make air travel ‘look' more expensive when in reality it's not.”

There’s also the potential for even more confusion, said Steve Lott, spokesman for the industry trade group Airlines for America. “When people hear ‘fees,’ they think it refers to fees for baggage, Wi-Fi or other airline fees,” he told msnbc.com. “It really just refers to the government fees and taxes.”

Nilou Motamed of Travel + Leisure magazine talks about new regulations that will go into effect this week, mandated by the Department of Transportation, and how they will affect your travel.

Potential confusion and pending lawsuits aside, the airlines are expected to comply with the full-fare advertising rule, as well as several others that took effect on Jan. 24, including a requirement allowing travelers to cancel reservations within 24 hours without penalty and a prohibition against post-purchase price increases.

On the other hand, the airlines received something of a break on pending rules requiring that travelers’ specific bag fees be disclosed on their e-ticket confirmations and mandating fee consistency across multiple carriers on interline and code-share flights.

Earlier this month, DOT denied an industry request to postpone those rules but noted that it would not strictly enforce them for six months.

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Rob Lovitt is a longtime travel writer who still believes the journey is as important as the destination. Follow him at Twitter.