|Locale||Maine, Vermont, Quebec|
|Dates of operation||May 2014–present|
|Predecessor||Montreal, Maine and Atlantic Railway|
|Track gauge||4 ft 8 1⁄2 in (1,435 mm) standard gauge|
|Length||481.01 miles (774.11 km)|
|Headquarters||New York, NY|
The Central Maine & Québec Railway ( reporting mark CMQ)  is a Class III freight railroad operating in the U.S. states of Maine and Vermont and the Canadian province of Quebec with headquarters in New York, NY. It is owned by Railroad Acquisition Holdings, LLC, a subsidiary of Fortress Investment Group, LLC.
Its United States operations are named the Central Maine & Québec Railway US Incorporated with offices in New York, NY, and was registered with the Surface Transportation Board on February 14, 2014. 
The Montreal, Maine and Atlantic Railway ( reporting mark MMA), itself a product of the 2002 Iron Road Railways bankruptcy, declared bankruptcy in the United States and Canada on August 7, 2013, following the fiery Lac-Mégantic derailment, in which a runaway crude oil train killed forty-seven people and caused an estimated $200 million in property damage to downtown Lac-Mégantic, Quebec. The company received protection under Chapter 11 of the United States Bankruptcy Code and under the Companies' Creditors Arrangement Act in Canada to oversee the sale of assets.  
In December 2013, Fortress Investment Group, LLC, through its subsidiary Railroad Acquisition Holdings, LLC (RAH) placed a stalking horse bid on the operating rail lines, which was accepted by the bankruptcy trustee in January 2014. In February 2014 RAH announced that it had formed the CMQ to become the operating entity of the rail lines and that the sale would be concluded in March 2014. CM&Q received its certificate of fitness from the Canadian Transportation Agency on June 24, 2014. 
In March 2014, John E. Giles of RAH drove the length of the line, visiting communities and industries served by the railway and inspecting the condition of tracks and installations. He estimated a $10–20 million investment would be needed over three years to repair the rail line, currently in poor condition and not safe for the transport of oil or dangerous goods. 
In August 2015, 15 empty boxcars of a CMQR freight train derailed at a siding in Farnham, Quebec. 
In September 2015, the CMQR was selected by the Maine Department of Transportation to operate the state-owned Rockland Branch rail line between Brunswick and Rockland, taking over the line from previous operator Maine Eastern Railroad on January 1, 2016.  The CMQ proposal did not account for the operation of passenger excursions that had been operated by Maine Eastern, ending 11 years of successful operations along the Maine coast.
The CMQ owns and operates the following rail lines:
- Searsport Subdivision (29 mi (47 km) Northern Maine Junction, ME to Searsport, ME)
- Millinocket Subdivision (78.5 mi (126.3 km) Northern Maine Junction, ME to Millinocket, ME)
- East Millinocket Subdivision (6.19 mi (9.96 km) Millinocket, ME to East Millinocket, ME)
- Madawaska Subdivision (1.5 mi (2.4 km) Millinocket, ME to start of Maine Northern Railway ( reporting mark MNRY))
- K.I. Subdivision (3.74 mi (6.02 km) Brownville, ME to Brownville Junction, ME)
- Moosehead Subdivision (117.1 mi (188.5 km) Brownville Junction, ME Lac-Mégantic, QC)
- Sherbrooke Subdivision (125.6 mi (202.1 km) Lac-Mégantic, QC to Brookport, QC)
- Adirondack Subdivision (20.0 mi (32.2 km) Brookport, QC to St-Jean-sur-Richelieu, QC)
- Newport Subdivision (60.4 mi (97.2 km) Brookport, QC to Newport, VT)
- Stanbridge Subdivision (12.57 mi (20.23 km) Farnham, QC to Stanbridge, QC)
- St-Guillaume Subdivision (26.4 mi (42.5 km) Farnham, QC to Sainte-Rosalie, QC)
CMQ owns a total of 481.01 mi (774.11 km) of rail line which are broken down by jurisdiction as follows:
- 220.73 mi (355.23 km) in Maine
- 236.81 mi (381.11 km) in Quebec
- 23.47 mi (37.77 km) in Vermont
- Canadian National Railway ( reporting mark CN)
- Canadian Pacific Railway ( reporting mark CP)
- Eastern Maine Railway ( reporting mark EMRY)
- Maine Northern Railway ( reporting mark MNRY)
- Pan Am Railways ( reporting mark ST)
- St. Lawrence and Atlantic Railroad ( reporting mark SLR) / ( reporting mark SLQ)
- Washington County Railroad ( reporting mark WACR)
- "FindUs.Rail | Search MARKs". Railinc. Retrieved 20 May 2014.
- "FORTRESS INVESTMENT GROUP LLC -CONTINUANCE IN CONTROL EXEMPTION- FLORIDA EAST COAST RAILWAY, L.L.C. AND CENTRAL MAINE & QUEBEC RAIL WAY US INC" (PDF). Surface Transportation Board. Retrieved 20 February 2014.
- "CENTRAL MAINE AND QUEBEC RAILWAY CANADA INC". Révenu Québec, Registraire des entreprises Québec. Retrieved 20 February 2014.
- "Maine-based railway involved in Quebec crash that killed 47 files for bankruptcy". Bangor Daily News. 2013-08-07. Retrieved 2013-08-08.
- Kim Mackrael (2013-08-07). "MM&A files for bankruptcy after Lac-Mégantic rail disaster". The Globe and Mail. Archived from the original on 2013-08-08. Retrieved 2013-08-07.
- "Canadian regulators approve sale of bankrupt Maine railway - The Portland Press Herald". 25 June 2014.
- Le futur propriétaire de MMA veut maintenir un lien de confiance, Rémi Tremblay, L'Echo de Frontenac (March 20, 2014)
- "Freight train derailment in Farnham, Que. investigated by Transportation Safety Board".
- Sharp, David (2013-07-09). "Railroad hopes town where 47 died will allow oil trains". The Portland Press Herald. Retrieved 2014-06-16.
- "Lac-Mégantic new rail owner plans to restart oil shipments". CBC News. 2014-05-16. Retrieved 2014-06-16.
- "Central Maine & Quebec to take over route of Maine Eastern". Trains Magazine. September 3, 2015. Retrieved September 3, 2015.