After a tight opening 25 minutes at Cusack Park, Mullingar, Westmeath led 2-8 to 0-10 at the interval, thanks to goals from Aonghus Clarke and Robbie Greville.
Antrim, backboned by U21 players, stayed in touch thanks to the free-taking of Ciaran Clarke, but a stronger, fitter Westmeath sealed their final place when Davy Gavin goaled in the 63rd minute.
Scorers for Westmeath: N. Conaty 0-8, (0-7 from frees), R. Greville 1-2, A. Clarke, D. Gavin 1-0 each, C. Curley, E. Price, A. McGrath 0-2 each, G. Greville 0-1.
Scorers for Antrim: C. Clarke 0-8, (0-6 frees, 0-1 ’65), Conor Johnson 0-3, S. McAfee 0-3 (0-1 free), R McCambridge, M. Dudley, M. Bradley 0-1 each.
WESTMEATH: P. Maloney; P. Fennell, T. Doyle, L. Varley; G. Greville, T. Gallagher, P. Reilly; E. Price, P. Gilsenan; R. Greville, D. Gavin, C. Curley; N. Conaty, A. McGrath, A. Clarke.
Subs: K. Duncan for P. Fennell (27), S. Fagan for P. Gilsenan (49), K. Glennon for C. Curley (55), S. Savage for R. Greville (injured, 67).
ANTRIM: C. Heyden; T. Ó Ciarain, E. Campbell, M. Bradley; D. McGuinness, Ciaran Johnson, S. Dooey; J. McGreevy, M. Dudley; S. McAfee, N. McKenna, T. Morgan; Conor Johnson, R. McCambridge, C. Clarke.
Subs: B. McFaul for N. McKenna (40), S. Rooney for D. McGuinness (40), C. Burke for S. Dooey (53), D. Kearney for M. Dudley (67).
Referee: Anthony Stapleton (Laois).