Delta Air Lines is shaking up its boarding process, ditching zone boarding for boarding by ticket type.

The Atlanta based carrier is renaming, and even color coding, its boarding groups, and increasing the number per flight from six to seven or eight depending on the aircraft. The goal: a smoother, more clear-cut boarding process.

Airlines are always testing and tinkering with boarding systems in a bid to lessen passenger frustration and gate crowding. United Airlines recently reduced the number of boarding groups on its flights.

“Every customer values consistency and a sense of knowing what to expect when they’re traveling,” Tim Mapes, Delta’s Senior Vice President and Chief Marketing Officer, said in a news release announcing the changes Tuesday. “We have been listening to our customers about the stress they often feel at the gate before boarding, and implementing small changes for years. This latest enhancement further refines how Delta’s process works.”

Delta says its changes will begin Jan. 23 on Delta flights around the world.

Flying in Delta's cushiest cabin, the pricey Delta One suites on select international and transcontinental flights? You'll board first (after pre-boarders), in the new Delta One boarding group instead of being lumped in with first class and Delta premium select passengers in in the current "premium'' boarding zone.

First class and premium select passengers will be the next group, called the first class and premium select boarding group.

Next up: Travelers who pay extra for or are upgraded to Delta's Comfort Plus seats, which are at the front of the main cabin and offer extra leg room, complimentary drinks and dedicated overhead bin space.

They get their own new boarding group, jumping ahead of certain Delta frequent flyers in the boarding pecking order, a move that is sure to rile some travelers. Currently, Delta Comfort Plus passengers are lumped in with certain levels of frequent flyers in a broad "Sky Priority'' group.

Delta says its gate agents recommended the addition of the Comfort Plus boarding group to reduce gate crowding. The airline tested it in Atlanta for two months and said travelers found it easier to board with their "branded fare" group.

The new Sky Priority boarding group, made up of travelers with platinum or gold medallion status in Delta's Sky Miles program, will follow Comfort Plus passengers on board. (Delta's top tier frequent flyers, Diamond Medallion members, board with Delta One or First Class, depending on the aircraft, under the new system.)

Main cabin passengers come next and will notice the least amount of change. Instead of having boarding zone 1, 2 or 3 printed on their boarding pass it will say Main Cabin 1, 2, or 3. Delta's lowest frequent flier tier, silver, and certain credit card holders will board with the Main Cabin 1 group.

Travelers who buy Delta's cheapest tickets, the no frills basic economy fare, will continue to board last, in the new basic economy boarding group. They are currently in zone 4. Unlike United, Delta allows a free carry-on bag for basic economy passengers, though travelers have to check them at the gate on many flights as overhead bin space fills up.