A pair of 18-darters from Mike Feaver got them off to a winning start.
But despite Ross Hughes hitting 180 in the next, he couldn’t beat Lee Smith, who registered a maximum and 18-dart leg.
John Madgwick and Darren Barnes put Chichester 3-1 up only for Bradley Mulholland and Jamie Stewart to restore parity again.
Mulholland and Stewart hit an 18-darter and 180, respectively.
But it was one-way traffic from there on as Dean Charman, Kevin Gilchrist, with an 18-darter, and Dean Jones booked Chichester’s place in the final.
Stag B will be their opponents after a 5-4 win over Druids Arms A.
Druids took a 3-1 lead courtesy of Darren Maplesden, Brian Dickson and Neil Hallett, with only David Place Jnr able to muster a response.
Stag hit back through Duncan Cope, James Scammell and Danny Browne to take the lead.
But Charlie Hymers won the penultimate clash to force a decider, which Dave Smith won.
Artillery Arms came from behind to beat Clarence Gardens 5-4 in the Ron Neale Shield semi-finals.
Dan Shambrook, with a 17-dart leg, and Leigh Rawlings put Clarence 2-0 up.
But Darrell Manchip’s 18-darter, along with wins for Jim Adams and Roy Morran moved Artillery 3-2 ahead.
Clarence regained the lead through James Miller and John Richmond.
But a 15-darter from Shane Filleul and win from Steve Woodage saw Artillery into the final.
They will meet George & Dragon, who beat Old House at Home 5-4.
Peter Neale won the opener but Mark French, with a 107 finish, Mike McKnight, Les Phipps, Gareth Young and Liam Emery gave George an insurmountable lead.
John O’Shea, Ian Sprake and Bradley Gilmour won consolations for House.
Jolly Taxpayer paid the price for turning up three players short in their Pompey Cup semi-final against Mermaid.
Only Dave Clarke and Alex Adams could muster wins, while Arnie Le Rouge, Gary Hornby, Stuart Edwards and Ryan Edwards helped Mermaid through.
Fellow finalists Harvest Home beat Graham Arms 6-3 with David Churcher, David King, Phil King, Ben Mowatt, Bill Bevan and Paul Henty on target.