A child's chances of leaving primary school with a good grounding in reading, writing and arithmetic still depend heavily on where they live, official statistics suggest.
In some areas of England, the vast majority of youngsters gain a Level 4 - the standard expected of 11-year-olds - in national curriculum tests in the basics, whereas in others, up to three in 10 fail to reach this target.
Overall, the proportion of primaries failing to ensure pupils reach a good standard in three Rs has remained static this year, despite schools facing tougher Government targets.
More than 700 schools in England are considered below the floor standard, the same proportion as last year, according to a Government analysis of data used to create primary school league tables.
Schools minister David Laws said the findings show schools have "raised their game", but warned there are still too many areas with "simply unacceptable" levels of attainment for poorer pupils.
Schools that fail to meet the benchmark - based on national curriculum test results at age 11 and pupil progress - are considered under-performing and at risk of being turned into an academy, or taken over by a different sponsor or trust if they already have academy status.
The Department for Education's (DfE) analysis shows wide variations across the country, with no schools under-performing in some areas while in others, significant proportions are below the Government's target. In one area, more than a quarter of primaries are considered to be under the threshold.
Under the Government's tougher standards, schools must ensure at least 65% of 11-year-olds reach Level 4 - the standard expected of the age group - in reading, writing and maths, and meet national averages in pupil progress.
Children working at Level 4 are considered able to spell, use joined-up handwriting, are beginning to use complex sentences, can calculate simple fractions and percentages and can multiply and divide whole numbers by 10 and 100.
Overall, 768 schools failed to meet the floor standard this year, compared with 767 last year, the DfE said.
The analysis shows 22 local authorities where there are no primary schools below the Government's floor target.
These are Blackpool, Camden, City of London, Greenwich, Haringey, Havering, Hillingdon, Hounslow, Isles of Scilly, Kingston upon Thames, Lewisham, Newham, North Tyneside, Redbridge, Richmond upon Thames, Southend-on-Sea, St Helens, Sutton, Torbay, Tower Hamlets, Westminster and Wokingham.
At the other end of the scale, there are 13 local authorities where more than one in eight primaries are below the floor.
In Poole, more than a quarter of primaries (27%) are below the standard, along with 18% in Rutland and Reading, 17% in Walsall, 16% in Barnsley, 15% in Suffolk, Isle of Wight and Derby, and 13% in Bournemouth, Bradford, Bristol, Peterborough and Southampton.
Based on pupil attainment in reading, writing and maths alone, without including progress measures, the top performing local authority was the City of London, with 93% of youngsters achieving Level 4 or above in all areas, followed by Richmond upon Thames, Sutton and Trafford each with 87%.
The worst was Luton, where 70% of youngsters got a Level 4 or above, followed by Rutland at 71% and Poole at 72%.
The new rankings are based on the performance of around 16,000 primaries in national curriculum tests - known as Sats - in reading and maths, as well as teacher assessments of pupils' writing skills.
The results also show:
:: The top primary school again this year, based on average points score, was Fox Primary School in Kensington and Chelsea, west London
:: Overall, 79% of 11-year-olds achieved the expected standard in all three areas this year, up three percentage points
:: The proportion of poorer children reaching at least Level 4 has risen by six percentage points to 67% in the last two years
:: The gap between richer and poorer pupils has narrowed by two percentage points between 2012 and 2014
:: To meet the Government's floor standard last year, primaries had to have 60% of 11-year-olds reaching Level 4 in each of the three key areas, as well as meeting the progress goals. According to the DfE's analysis, if primary schools were judged on this year's data against 2013's target, only 469 schools would have fallen below the threshold
Mr Laws said: "I am pleased to see that primaries have responded to the challenge of a higher floor standard - we have raised the bar and schools have raised their game.
"It is also encouraging to see the attainment gap between disadvantaged children and their peers continue to narrow and parents, teachers and pupils deserve to be congratulated for their efforts."