After three years in Division 2, victory over Pat Flanagan’s side ensured that Derry topped the league, an added boost at the end of a successful league campaign.
Two superbly taken penalties by James Kielt were the key scores for the Oak Leafers against the visitors, who were too wasteful in the first half to make a dent in the arrears.
With the first half in stoppage time, sub Benny Heron was pulled down by Damian Dolan and Kielt dispatched the penalty to send Derry in 1-6 to 0-3 ahead.
Eoin Bradley and Lee Kennedy pointed on the restart, though hopes of a Westmeath revival came through a brilliant goal from centre-back Paul Sharry, who had been denied one in the first half by the knees of Eoin McNicholl.
No sooner had it nestled in the net than Derry were on the counter and Kielt was needlessly bundled over by keeper Eoin Carberry, resulting in a second penalty for the home side.
Kielt went to the other side, and again Carberry guessed right, but the Kilrea man’s spot-kick was inch-perfect into the top left hand corner.
The result saw Derry finish as the highest league scorers in the country and sends them into the Croke Park decider as favourites, though Westmeath’s side will look a lot different on April 28.
Scorers for Derry: J Kielt 2-1 (2-0p), E Bradley 0-5 (2fs), L Kennedy 0-3 (1f), R Bell 0-2, A McAlynn, C McKaigue, C Devlin, E Lynn, R Wilkinson, C Kielt 0-1.
Scorers for Westmeath: D Dolan 0-3 (2fs), P Sharry 1-0, D Corroon, K Martin 0-1.
DERRY: E McNicholl; A McAlynn, C McKaigue, M Bateson; C Kielt, G O’Kane, SL McGoldrick; P Bradley, R Bell; D Heavron, J Kielt, E Lynn; R Wilkinson, E Bradley, L Kennedy.
Subs: B Heron for Bateson (34), C Devlin for Kennedy (48), E McGuckin for Wilkinson (60), G Mallon for P Bradley (61), B McCallion for O’Kane (64).
WESTMEATH: E Carberry; J Gaffey, M McCallon, K Maguire; D Dolan, P Sharry, D Harte; D Duffy, D Daly; D Mullan, P Bannon, D Corroon; R Foley, L Smyth, D Dolan.
Subs: G Egan for Mullan (52), K Martin for Bannon (52), C McCormack for Foley (52), P Sheridan for Corroon (61), C Curley for Dolan (66).
Referee: C Brannigan (Down).