Eight local councils - including several in party heartland - will go to upcoming statewide elections without a Liberal candidate on the ticket after the party failed to submit nominations by midday on Wednesday.
Another nine have only partial coverage, according to analysis of the Liberals' own-goal.
Would-be candidates found out after it was too late to handle nominations for the September council poll themselves.
Opposition Leader Mark Speakman called for party state director Richard Shields to quit after "the worst act of mismanagement that I can think of in the organisation's history" in an email to colleagues on Thursday.
"It's a basic matter of competence and administration," he told reporters.
"If you don't have the resources to handle these nominations, you call for more.
"And if you're still not satisfied there are enough resources, you let the candidates nominate themselves."
While denying it was a sign the party had lost its way, Mr Speakman said the "monumental stuff-up" would have ongoing ramifications.
"It's well known that major parties often draw from local councillors for state and federal candidates," he said.
Bewildered deputy NSW Liberal leader Natalie Ward said the state director only had two jobs: administer the party constitution and administer electoral matters.
"He didn't give appropriate notice that anybody else needed to help," the senior state MP said.
Deputy leader Natalie Ward says not enough notice was given that help was needed. (Bianca De Marchi/AAP PHOTOS)
Federal party leader Peter Dutton also expressed disappointment, adding he hoped the NSW branch could sort out the mess.
"I would suggest there needs to be at least two resignations," he told Sydney radio 2GB.
Northern Beaches, Lane Cove, Camden and Campbelltown councils are among those affected in Sydney, while the regional local government areas of Cessnock, Wollongong, Shoalhaven and Blue Mountains are also affected.
Several councils overlap with safe Liberal seats in state parliament.
Election analyst Ben Raue said he had counted 45 contests where Liberals were expected to nominate but had either failed to do so or nominated too few candidates to get a party grouping, totalling 136 candidates.
Polls in those areas could have elected about 52 Liberals, but now only about four party candidates had a realistic chance, the creator of the website TallyRoom said.
The mess also means a ward in Penrith - where 10,000 voters chose Liberal at the last election - will be uncontested after Labor nominated the only candidates.
"That election is over, today," Mr Raue told AAP.
Peter Dutton said there should be at least two resignations. (Mick Tsikas/AAP PHOTOS)
A Liberal party insider contested Mr Raue's figures, suggesting the mess extended to only about two dozen winnable seats.
The "unbelievable" blunder led Liberal Lane Cove mayor Scott Bennison to quit the party on Thursday, saying he was "sick of all the factional rubbish".
Mr Shields, a mayor, has blamed his mistake on a lack of resources and apologised to the Liberal-endorsed candidates who have not been nominated.
But he had withstood calls for his resignation on Thursday morning.
More than four million NSW voters will go to the polls on September 14, electing more than 1000 councillors to local government.
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