Overall, the market topped 1.4 million cars, an increase over last year's 1.25 million, and a continued sign of economic recovery.
The biggest gainer was Chrysler, which has continued momentum for all of its lines - Chrysler division, Jeep, Ram and Dodge - ever since it debuted a number of heavily refreshed or revised models just over a year ago.
Check out the detailed numbers below and keep reading for our analysis of the market.
Note that we delayed releasing monthly sales figures in order to concentrate on the New York International Auto Show earlier this week. You can find our coverage of that major show here.
Acura - Down 12 percent to 11,166
Audi - Up 18 percent to 11,585
BMW - Up 18 percent to 23,940
Buick - Down 16 percent to 13,105
Cadillac - Down 13 percent to 10,537
Chevrolet - Up 17 percent to 173,073
Chrysler - Up 70 percent to 34,726
Dodge - Up 18 percent to 52,076
Fiat - Up 642 percent to 3,712
Ford - Up 5 percent to 214,615
GMC - Up 12 percent to 34,337
Honda - Down 4 percent to 115,833
Hyundai - Up 13 percent to 69,728
Infiniti - Down 10 percent to 10,185
Jaguar - Up 51 percent to 1,321
Jeep - Up 36 percent to 45,124
Kia - Up 30 percent to 57,505
Land Rover - Up 22 percent to 4,199
Lexus - Down 3 percent to 20,140
Lincoln - Up 4 percent to 8,803
Maserati - Up 29 percent to 257
Mazda - Up 5 percent to 32,376
Mercedes-Benz - Up 3 percent to 23,134
Mitsubishi - Down 5 percent to 7,160
MINI - Down 4 percent to 5,866
Nissan - Up 15 percent to 126,132
Porsche - Down 5 percent to 2,460
Ram - Up 18 percent to 27,743
Smart - Up 135 percent to 999
Subaru - Up 20 percent to 32,387
Suzuki - Up 5 percent to 2,631
Toyota (Includes Scion) - Up 18 percent to 183,142
Volkswagen - Up 35 percent to 36,588
Volvo - Up 5 percent to 6,693
BMW Group - Up 13 percent to 29,806
Chrysler - Up 34 percent to 163,381
Daimler - Up 11 percent to 25,512
Ford Motor Company - Up 5 percent to 223,418
General Motors - Up 12 percent to 231,052
American Honda - Down 5 percent to 126,999
Hyundai Group - Up 20 percent to 127,233
Jaguar Land Rover - Up 28 percent to 5,520
Nissan North America - Up 13 percent to 136,317
Toyota USA - Up 15 percent to 203,282
2012 YTD Numbers
Acura - Down 2 percent to 30,805
Audi - Up 16 percent to 29,470
BMW - Up 17 percent to 61,549
Buick - Down 17 percent to 37,336
Cadillac - Down 24 percent to 30,966
Chevrolet - Up 8 percent to 448,134
Chrysler - Up 85 percent to 79,338
Dodge - Up 24 percent to 126,222
Fiat - Up 1,670 percent to 8,850
Ford - Up 9 percent to 516,986
GMC - Up 1 percent to 91,884
Honda - Up 5 percent to 289,360
Hyundai - Up 15 percent to 163,573
Infiniti - Down 6 percent to 26,220
Jaguar - Up 33 percent to 3,328
Jeep - Up 35 percent to 114,146
Kia - Up 32 percent to 138,060
Land Rover - Up 29 percent to 10,659
Lexus - Up 4 percent to 49,096
Lincoln - Up 4 percent to 20,836
Maserati - Up 27 percent to 602
Mazda - Up 27 percent to 82,023
Mercedes-Benz - Up 16 percent to 64,649
Mitsubishi - Down 18 percent to 16,607
MINI - Up 15 percent to 14,180
Nissan - Up 15 percent to 296,141
Porsche - Up 2 percent to 7,159
Ram - Up 22 percent to 69,495
Smart - Up 79 percent to 2,264
Subaru - Up 19 percent to 15,171
Suzuki - Down 2 percent to 6,561
Toyota (Includes Scion) - Up 13 percent to 438,187
Volkswagen - Up 41 percent to 94,373
Volvo - Up 6 percent to 16,418
BMW Group - Up 17 percent to 75,825
Chrysler - Up 39 percent to 398,051
Daimler - Up 17 percent to 66,925
Ford Motor Company - Up 9 percent to 537,822
General Motors - Up 3 percent to 608,320
American Honda - Up 4 percent to 320,165
Hyundai Group - Up 22 percent to 301,633
Jaguar Land Rover - Up 30 percent to 13,987
Nissan North America - Up 13 percent to 322,361
Toyota USA - Up 12 percent to 487,283
General Motors continues to see weak demand this year for its more premium brands Cadillac and Buick, but Chevrolet is filling the gap in terms of volume. Truck, SUV and compact and midsize sedan sales were strongest, although the automaker should be pretty happy with the 8,251 Chevrolet Sonics that were delivered last month.
Ford, meanwhile, posted its best March in half a decade on strong months for the Fusion, Focus and Edge, all of which set March records. The boost in Focus sales was the most notable, however, since the compact sedan and hatchback range got off to a slow start when it was introduced last year. Lincoln also saw a modest increase thanks to a 59 percent jump in demand for the MKS.
Chrysler posted its best March since 2008. Its namesake division had the strongest overall month; the 200 sedan was Chrysler's second-best seller behind its Ram pickup last month.
Toyota's Camry was the country's best-selling four-door last month, but it was a 54 percent jump in Prius sales that looks the most impressive. However, it's worth noting that Toyota includes its new Prius C and Prius V models when it reports all Prius sales, even though the three are distinct vehicles.
Meanwhile, Nissan made headlines this week by unveiling a redesigned Altima, but that apparently didn't stop buyers from lining up last month for the old model. With more than 41,000 Altimas sold, Nissan broke an all-time monthly record for its midsize sedan.
At Honda, the redesigned CR-V had its best month ever, but the rest of the lineup suffered. Accord and Civic sales trickled off 18 and 13 percent, respectively, while even stalwarts like the Odyssey and Pilot had modest 2 and 1 percent gains.
Hyundai had its best March ever with improved sales for nearly every model in its lineup aside from the Tucson, Veracruz and Azera. Subaru's redesigned Impreza broke a - you guessed it - sales record
VW sold more than 10,000 Passats in March, which should easily put the sedan on the track to 100,000 units this year. The rest of VW's news was a bit mixed; Jetta sales were off 12 percent, while the Golf was up 17 percent.
BMW and Mercedes-Benz both posted their best first quarters ever in the U.S., which means their battle is likely to heat up even further.
Leftlane's bottom line
March was a solid month for mainstream models, although luxury brands suffered a bit. This is the opposite trend we've seen over the last couple of years, where premium models have recovered more quickly than non-premium vehicles, and it could represent a major shift in the market as a whole.
Chrysler certainly has reason to continue celebrating, but GM should be concerned about lagging sales at Buick. Toyota seems to be recovering nicely, while arch rival Honda can't seem to get its feet off the ground.
It's worth noting that the next few months should be a wild ride, at least as far as the numbers are concerned, since sales of Japanese cars tanked in response to limited supply caused by last year's devastating tsunami. Stay tuned!