- NATwA Singles Championships
- NATwA Pairs Championships
- NATwA Continentals (team championships)
North American Singles
| Year | Venue | Champion Single | Top National (if champion is not US) | 2nd | 3rd |
| 1972 | Lake Mohegan NY | Bob Henninge | ∅ | Severin Drix | Bill Renke |
| 1973 | Lake Mohegan NY | Bill Renke | ∅ | Ross Callon | Bob Henninge |
| 1974 | Cambridge MA | Severin Drix | ∅ | Ross Callon | Dave Lockwood |
| 1975 | Cambridge MA | Severin Drix | ∅ | Ferd | Jim Marlin |
| 1976 | Cambridge MA | Sunshine | ∅ | Dave Lockwood | Jim Marlin |
| 1977 | Silver Spring MD | Dave Lockwood | ∅ | Bob Henninge | Severin Drix |
| 1978 | Baltimore MD | Dave Lockwood | ∅ | Bob Henninge | Larry Kahn |
| 1979 | Cambridge MA | Severin Drix | ∅ | Joe Sachs | Dave Lockwood |
| 1980 | Silver Spring MD | Pam Knowles | ∅ | Larry Kahn | Dave Lockwood |
| 1981 | Cambridge MA | Larry Kahn | ∅ | Arye Gittelman | Dave Lockwood |
| 1982 | Cambridge MA | Larry Kahn | ∅ | Arye Gittelman | Severin Drix |
| 1983 | Cambridge MA | Dave Lockwood | ∅ | Arye Gittelman | Severin Drix |
| 1984 | College Park & Gaithersburg MD | Arye Gittelman | ∅ | Larry Kahn | Dave Lockwood |
| 1985 | Silver Spring MD | Larry Kahn | ∅ | Dave Lockwood | Arye Gittelman |
| 1986 | (not played) | ∅ | |||
| 1987 | Cambridge MA & Silver Spring MD | Larry Kahn | ∅ | Dave Lockwood | Rick Tucker |
| 1988 | Falls Church VA | Larry Kahn | ∅ | Geoff Myers | Jon Mapley |
| 1989 | Silver Spring MD | Larry Kahn | ∅ | ||
| 1990 | Falls Church VA | Andy Purvis (UK) | Larry Kahn, 2nd | Larry Kahn | |
| 1991 | Silver Spring MD | Larry Kahn | ∅ | ||
| 1992 | Silver Spring MD & Ashburn VA | Dave Lockwood | ∅ | ||
| 1993 | Ashburn VA | Andy Purvis (UK) | Dave Lockwood, 3rd | Jon Mapley | Dave Lockwood |
| 1994 | Wheaton MD | Larry Kahn | ∅ | ||
| 1995 | Vienna VA | Dave Lockwood | ∅ | ||
| 1996 | Vienna VA (played in 1997) | Larry Kahn | ∅ | ||
| 1997 | Vienna VA | Larry Kahn | ∅ | ||
| 1998 | Ashburn VA | Larry Kahn | ∅ | ||
| 1999 | Larry Kahn | ∅ | |||
| 2000 | Larry Kahn | ∅ | |||
| 2001 | Great Falls & Vienna VA | Dave Lockwood | ∅ | ||
| 2002 | Ithaca NY | Larry Kahn | ∅ | ||
| 2003 | Larry Kahn | ∅ | |||
| 2004 | Larry Kahn | ∅ | |||
| 2005 | Larry Kahn | ∅ | |||
| 2006 | Silver Spring MD | Larry Kahn | ∅ | ||
| 2007 | Larry Kahn | ∅ | |||
| 2008 | Vienna VA | Larry Kahn | ∅ | ||
| 2009 | Vienna VA | Larry Kahn | ∅ | ||
| 2010 | Larry Kahn | ∅ | |||
| 2011 | Larry Kahn | ∅ | |||
| 2012 | Vienna VA | Larry Kahn | ∅ | Bob Henninge | Ferd Wulkan |
| 2013 | Vienna VA | Larry Kahn | ∅ | ||
| 2014 | Vienna VA | Larry Kahn | ∅ | ||
| 2015 | Vienna VA | Larry Kahn | ∅ | ||
| 2016 | Vienna VA | Larry Kahn | ∅ | ||
| 2017 | Vienna VA | Larry Kahn | ∅ | ||
| 2018 | Vienna VA | Larry Kahn | ∅ | Dave Lockwood | Jon Lockwood; Ferd Wulkan (tie) |
| 2019 | Vienna VA | Larry Kahn | ∅ | Dave Lockwood | Bob Henninge |
| 2020 | (not played due to COVID-19) | ∅ | ∅ | ||
| 2021 | (not played due to COVID-19) | ∅ | ∅ |
North American Pairs
| Year | Venue | Champion Pair | Top Nationals | 2nd | |
| 1970 | Ithaca NY | Ferd & Bob Henninge | ∅ | Rosie Wain & Andy Tomaszewski | |
| 1971 | Ottawa, Ontario | Ferd & Bob Henninge | ∅ | Severin Drix & Phil Villar | |
| 1972 | Cambridge MA | Severin Drix & Andy Tomaszewski | ∅ | Craig Schweinhart & Ross Callon | |
| 1973 | Cambridge MA | Bill Renke & Ross Callon | ∅ | Bob Henninge & Betsy Smith | |
| 1974 | Cambridge MA | Bill Renke & Ross Callon | ∅ | Sunshine & Severin Drix | |
| 1975 | Cambridge MA | Dave Lockwood & Severin Drix | ∅ | Ferd & Don Fox | |
| 1976 | Cambridge MA | Severin Drix & Larry Kahn | ∅ | Dave Lockwood & Indian | |
| 1977 | Cambridge MA | Severin Drix & Larry Kahn | ∅ | Sunshine & Ferd | |
| 1978 | Ithaca NY | Severin Drix & Larry Kahn | ∅ | Bob Henninge & Mary Kirman | |
| 1979 | Ithaca NY | Severin Drix & Joe Sachs | ∅ | Sunshine & Bob Henninge | |
| 1980 | Cambridge MA | Larry Kahn & Arye Gittelman | ∅ | Bill Renke & Ross Callon | |
| 1981 | Ithaca NY | Larry Kahn & Severin Drix | ∅ | Ross Callon & Arye Gittelman | |
| 1982 | Ithaca NY | Joe Sachs & Charles Frankston | ∅ | Sunshine & L | |
| 1983 | Ithaca NY | Larry Kahn & Arye Gittelman | ∅ | Joe Sachs & Charles Frankston | |
| 1984 | Ithaca NY | Larry Kahn & Arye Gittelman | ∅ | Severin Drix & Rick Tucker | |
| 1985 | Ithaca NY | Larry Kahn & Arye Gittelman | ∅ | Brad (solo) | |
| 1986 | (not played) | ∅ | |||
| 1987 | Ithaca NY | Dave Lockwood & Larry Kahn | ∅ | Severin Drix & Jim Marlin | |
| 1988 | Cambridge MA | Dave Lockwood & Jim Marlin | ∅ | Larry Kahn & Rick Tucker | |
| 1989 | Ithaca NY | Dave Lockwood & Jim Marlin | ∅ | Larry Kahn & Rick Tucker | |
| 1990 | Glouster OH | Bob Henninge & Larry Kahn | ∅ | ||
| 1991 | Ashburn VA | Dave Lockwood & Rick Tucker | ∅ | ||
| 1992 | Dedham MA | Arye Gittelman & Larry Kahn | ∅ | ||
| 1993 | Arye Gittelman & Larry Kahn | ∅ | |||
| 1994 | Boston MA | Arye Gittelman & Larry Kahn | ∅ | ||
| 1995 | Cleveland Heights OH | Dave Lockwood & Brad Schaefer | ∅ | ||
| 1996 | Vienna VA | Larry Kahn & Rick Tucker | ∅ | ||
| 1997 | (not played) | ∅ | |||
| 1998 | Ashburn VA | Patrick Barrie (UK) & Christine Wiggins (UK) |
Marg Calhoun & Larry Kahn, 2nd | Marg Calhoun & Larry Kahn | |
| 1999 | Ithaca NY | Severin Drix & Julian Drix | ∅ | ||
| 2000 | Ithaca NY | Larry Kahn & Marg Small | ∅ | ||
| 2001 | Ithaca NY | Dave Lockwood & Max Lockwood | ∅ | ||
| 2002 | Ithaca NY | Ferd & Mac McAvoy | ∅ | ||
| 2003 | Bob Henninge & Yan Wang | ∅ | |||
| 2004 | Wheaton MD | Larry Kahn & Prabhas Pokharel | ∅ | ||
| 2005 | Dave Lockwood & Jon Lockwood | ∅ | |||
| 2006 | Silver Spring MD | Larry Kahn & Max Lockwood | ∅ | ||
| 2007 | Prabhas Pokharel & Yan Wang | ∅ | |||
| 2008 | (played in 2009) | Larry Kahn & Jon Lockwood | ∅ | ||
| 2009 | Ithaca NY | Severin Drix & Larry Kahn | ∅ | ||
| 2010 | Vienna VA | Bob Henninge & Charles Relle | |||
| 2011 | Ithaca NY | Larry Kahn & Mac McAvoy | ∅ | ||
| 2012 | Ithaca NY | Larry Kahn & Jon Lockwood | ∅ | Bob Henninge & Alan Smith | |
| 2013 | Vienna VA | Patrick Driscoll (UK) & Larry Kahn | |||
| 2014 | Vienna VA | Larry Kahn & Mac McAvoy | ∅ | Patrick Driscoll (UK) & Rick Tucker | |
| 2015 | Vienna VA | Patrick Driscoll (UK) & Ferd Wulkan | |||
| 2016 | Vienna VA | Alan Dean (UK) & Ferd Wulkan | |||
| 2017 | Ithaca NY | Larry Kahn & Dave Lockwood | ∅ | ||
| 2018 | Ithaca NY | Larry Kahn & Dave Lockwood | ∅ | Alan Dean (UK) & Severin Drix | |
| 2019 | Ithaca NY | Larry Kahn & Dave Lockwood | ∅ | Alan Dean (UK) & Severin Drix | Bob Henninge & Ferd Wulkan |
| 2020 | (not played due to COVID-19) | ∅ | ∅ | ∅ | ∅ |
| 2021 | (not played due to COVID-19) | ∅ | ∅ | ∅ | ∅ |
Continentals (North American Teams)
| Year | Venue | Champion | 2nd | 3rd |
| 1967 | Waterloo | Cornell | Waterloo | MIT |
| 1968 | Ithaca NY | MIT | Toronto | Cornell |
| 1969 | Cambridge MA | MIT A | Cornell | Case |
| 1970 | Ithaca NY | Somerville | Cornell | |
| 1971 | Toronto | Somerville | MIT | Toronto |
| 1972 | Ithaca NY | MIT A | Cornell | Somerville |
| 1973 | Ithaca NY | Zoo | MIT A | HYTH |
| 1974 | Ithaca NY | HYTH | Zoo | Somerville |
| 1975 | Ithaca NY | Zoo | Somerville | MIT A |
| 1976 | Ithaca NY | Zoo | MIT | TKOs |
| 1977 | Ithaca NY | Renaissance | Zoo | Toads |
| 1978 | Cambridge MA | Renaissance | MIT | Chickenhearts |
| 1979 | Cambridge MA | Renaissance | Relix | Chickenhearts |
| 1980 | Ithaca NY | Relix | MIT | Moosewinks |
| 1981 | Haverford PA | Alliance | Relix | MIT |
| 1982 | Cambridge MA | Relix | Alliance | MIT |
| 1983 | Cambridge MA | Alliance | Chickens | MIT |
| 1984 | Cambridge MA | Alliance | Chickens | Toads |
| 1985 | Ithaca NY | BosWash | ||
| 1986 to present | (not played) |