They overcame Kildare while Laois lost out to Wexford.
It's back to back All-Ireland Intermediate deciders for Westmeath.
Sean Finnegan's side claimed a spot in the decider courtesy of a 3-6 to 1-9 victory over Kildare.
Sarah Dillon, Lucy McCartan and a 56th minute strike by Anna Jones supplied the goals that fired them to victory.
It brought Jones' tally to 1-3 on the day and was the final dagger in a spirited Kildare comeback.
The Lilywhites rallied from a deficit of six points down after the concession of two goals in the opening ten minutes of the contest.
The result sends Westmeath into yet another Croke Park showdown, having come up just short against Meath in the 2020 final.
Westmeath and Wexford will contest the All-Ireland Intermediate Ladies Football final
— Midlands 103 Sport (@MidlandsSport) August 15, 2021
We'll be joined by former Laois captain Mags McEvoy next
They'll face Wexford after the model county caused somewhat of an upset against Laois.
The O'Moore county were riding the crest of a wave entering the contest having secured promotion to division two of the league and some great performances in the championship.
They had to produce a different kind of display in this one as Wexford produced key scoring runs in both the first and second half, twice building up leads that Laois had to battle to reduce.
Both Laois green flags came in the opening 30 minutes from Emma Galvin and sharpshooter Mo Nerney.
Wexford however managed to rattle off five successive scores in the opening period and when Aisling Murphy nailed a crucial goal after 47 minutes to restore their five point advantage looked in pole position to advance.
Credit to Laois though as they displayed a battling quality in the closing stages, almost pulling off the comeback with three scores through Nerney and Ellen Healy.
It wasn't to be though and Donie Brennan's charges can now take time to reflect on a very positive season for ladies football in the O'Moore county.
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