Prior to the 2018 elections, one New York House seat was vacant[1] due to the death of Rep. Louise Slaughter (D-25th District) on March 16, 2018.

[2] In the June 26, 2018 Democratic primary in District 14, insurgent Alexandria Ocasio-Cortez upset longtime incumbent Rep. Joe Crowley.

[4] Incumbent Rep. Chris Collins (R-27th District) was narrowly re-elected[6] despite having been arrested on insider trading charges in August 2018.

The 1st district was included on the initial list of Republican-held seats being targeted by the Democratic Congressional Campaign Committee in 2018.

[26] At the end of September, the nonpartisan Washington, D.C.-based Cook Political Report rated the race as "Likely Republican;" the "Likely" designation is for seats "not considered competitive at this point, but hav[ing] the potential to become engaged.

"[27] U.S. Executive Branch officials Labor unions Organizations Newspapers Labor unions Organizations Newspapers Peter T. King Republican Peter T. King Republican The 2nd district is based along the South Shore of Long Island and includes southwestern Suffolk County and a small portion of southeastern Nassau County.

New York's 3rd district was included on the initial list of Democrat-held seats being targeted by the National Republican Congressional Committee in 2018.

Labor unions Dan Donovan Republican Max Rose Democratic The 11th district is located entirely in New York City and includes all of Staten Island and parts of southern Brooklyn.

Former Congressman Michael Grimm, who resigned in 2014 after pleading guilty to federal tax fraud charges for which he served eight months in prison, challenged Donovan in the primary.

Representatives State officials State legislators Labor unions Organizations Local officials Individuals Carolyn Maloney Democratic Carolyn Maloney Democratic The 12th district is located entirely in New York City and includes several neighborhoods in the East Side of Manhattan, Greenpoint and western Queens.

Crowley, who had been named as a potential successor to Nancy Pelosi as House Leader or Speaker, sought re-election in 2018.

[77] Backed by the organization Brand New Congress, bartender and activist Alexandria Ocasio-Cortez challenged Crowley in the primary, announcing her campaign in June 2017.

[80] Despite this, most observers concluded that Crowley would win the primary, citing his strong support from elected officials and his large fundraising advantage.

[79] In her campaign, Ocasio-Cortez claimed that Crowley was not progressive enough for the district,[81] and also accused him of corruption, stating that he was using his position as chair of the Queens Democratic Party improperly.

[78] She aggressively built a presence on social media platforms, creating a biographical video promoting her campaign that went viral.

Representatives Organizations Individuals Ocasio-Cortez defeated Crowley in the Democratic primary election, which was considered an upset victory.

[82] Following his defeat in the Democratic primary, Crowley remained on the ballot on the Working Families Party line, but did not actively campaign.

[95] Michael Rendino, chairman of the Bronx Republican Party, was more skeptical, declaring that "even if Crowley and Ocasio-Cortez split the vote, we'd still lose two-to-one".

[95] Pappas's campaign was based around the abolition of judicial immunity, which he argued had led to judges becoming unaccountable for their actions.

New York's 18th district was included on the initial list of Democratic held seats that were being targeted by the National Republican Congressional Committee in 2018.

[52] Labor unions John Faso Republican Antonio Delgado Democratic The 19th district is located in New York's Hudson Valley and Catskills regions and includes all of Columbia, Delaware, Greene, Otsego, Schoharie, Sullivan and Ulster counties, and parts of Broome, Dutchess, Montgomery and Rensselaer counties.

[116] New York's 19th district was included on the initial list of Republican-held seats being targeted by the Democratic Congressional Campaign Committee in 2018.

[12] Declared Disqualified[131] U.S. Executive Branch officials Organizations U.S. Executive Branch officials State legislators Labor unions Newspapers Paul Tonko Democratic Paul Tonko Democratic The 20th district is located in the Capital District and includes all of Albany and Schenectady Counties, and portions of Montgomery, Rensselaer and Saratoga Counties.

New York's 22nd district was included on the initial list of Republican-held seats being targeted by the Democratic Congressional Campaign Committee in 2018.

Representatives Labor unions Organizations Newspapers Tom Reed Republican Tom Reed Republican The 23rd district includes all of Allegany, Cattaraugus, Chautauqua, Chemung, Schuyler, Seneca, Steuben, Tompkins and Yates counties, along with parts of Ontario and Tioga counties.

Although Della Pia finished slightly ahead of the other candidates on primary election night, he conceded to Mitrano after absentee ballots were counted.

U.S. Executive Branch officials Organizations Newspapers Labor unions Newspapers Local officials John Katko Republican John Katko Republican The 24th district includes all of Cayuga, Onondaga and Wayne counties, and the western part of Oswego County.

New York's 24th district was included on the initial list of Republican-held seats being targeted by the Democratic Congressional Campaign Committee in 2018.

He was re-elected to a third term with 67% of the vote in 2016, New York's 27th district was included on the initial list of Republican-held seats being targeted by the Democratic Congressional Campaign Committee in 2018.

Removing himself from the ballot would have required Collins to be nominated as a dummy candidate in another election or to move his legal place of residence out of state (he has additional homes in Florida and the District of Columbia).