The Atlanta & West Point operated a total of six Mikados of different design, which were designated class F. The first two, numbered 400 and 401, were built in 1918 by Lima. They were of the Harriman Common Standard Mikado design and were built together with two for the Western Railway of Alabama. Three more were built by Lima between 1923 and 1925 which received the numbers 425 to 427. But these were copies of the USRA Light Mikado and again, the Western Railway of Alabama got four from the same batch.

No. 430, built by Baldwin in 1944, was an updated USRA Heavy Mikado copy. Together with another locomotive for the Western Railway of Alabama, they were among the last Mikados built for a US railroad. The total surface in the firebox was much bigger with 57 square feet in the combustion chamber, two thermic syphons of 40 square feet each and 14 square feet in arch tubes. 400 and 401 were retired in 1951 and the others followed between 1952 and 1954.

In 1918, the Seaboard Air Line received 16 2-8-8-2 Mallets from ALCO-Richmond to move fast, heavy freights on their main line between Richmond, Virginia and Hamlet, North Carolina. After the wartime traffic had ended, it became clear that the SAL didn't have many uses for them since they were too heavy for many of their secondary lines and didn't fit the clearances in many places.

So all were sold to the B&O in 1920 and only two years later, they were rebuilt to class EL-6a. In this process, they got the wheel arrangement 2-8-8-0 by removing the trailing axle. This considerably increased the adhesive weight and at the same time they were simpled and got a higher boiler pressure, what also increased their starting tractive effort. In this form, they were used until 1954.

The class D-3 consisted of eight light Decapods built in 1930 for the Seaboard Air Line. They were ordered after the SAL had leased the Georgia, Florida & Alabama in 1927 and found out about the versatility of their six light Decapods. Actually, the new ones were virtually identical and could deliver high tractive efforts on branch lines with an axle load of only 19 tons. They were numbered 529 to 536 and retired in 1952 and 1953. After that, the Gainesville Midland bought a total of seven of both the original and the new class. No. 209, the original SAL 533, was preserved and is on display at Gainesville.

After the Seaboard Air Line had already put ten USRA Light Mikados into service as class Q-1, a total of 117 copies were built as the Q-3 from 1923 onwards. They differed from the USRA locomotives primarily in the firebox and had a longer wheelbase between the leading axle and the first driver. They also had a mechanical stoker and a booster on the trailing axle. After the 117 locomotives had been built by ALCO and Baldwin by 1926, the SAL manufactured number 451 in its own workshops in 1930. This was created from the frame of 441, which had fallen victim to a boiler explosion. The last Q-3 disappeared in 1955.

The class T60-I4, numbered 552 to 568, were 17 4-6-0 freight locomotives built by the Pittsburgh Locomotive Works in 1896. Designed by W.T. Reed, they had small drivers of 58 inches and cylinders of 19 by 24 inches. No. 559 was sold to the Raleigh & Charleston in 1917. Of the other 16 locomotives, around one half was retired in 1922 and 1923 and the rest between 1928 to 1930.

The Seaboard Air Line operated ten 2-6-6-4 articulated locomotives built by Baldwin in two batches of five in 1935 and 1937. Although smaller than the Norfolk & Western class A, they were still substantial locomotives, weighing 480,000 pounds without tender and 790,200 pounds in working order. The boiler featured a 96.3-square-foot grate and a 515-square-foot firebox equipped with two thermic syphons and a long combustion chamber. Heating surface amounted to 4,998 square feet in the tubes and flues and 2,397 square feet in the superheater. 

The first batch, class R-1 (Nos. 2500–2504), was fitted with Baker valve gear and an Elesco feedwater heater. The second batch, class R-2 (Nos. 2505–2509), differed in having Walschaerts valve gear, a Worthington feedwater heater, and 38 rather than 44 boiler tubes. Like many articulated locomotives with three coupled axles per engine unit, they were prone to slipping on the leading engine.

All ten locomotives were sold to the Baltimore & Ohio in August 1947. The R-1 locomotives became class KB-1, numbered 7700–7704, while the R-2 locomotives were classified KB-1a and renumbered 7705–7709. The B&O reportedly had to address persistent leakage problems in the flexible steam joints supplying the front engine unit. In service they proved less popular than the S-1 2-10-2s, which developed almost identical starting tractive effort while being less susceptible to wheel slip. The entire class was withdrawn and scrapped in May and June 1953.