Essex has been identified as the county with the largest pension pots for annuities with the average total pot size standing at £125,478, according to data analysis.
Based on almost 2,500 customers who took out an intermediated pension, annuity provider Partnership reported Surrey followed closely behind with the average size standing at £123,788. This was followed by Hertfordshire, at £123,158.
The analysis also found Shropshire had the smallest pots (£44,336), followed by Northumberland (£53,538) and South Yorkshire (£56,736). Across the UK, the average annuity pot is worth £87,724.
Andrew Megson, managing director of retirement at Partnership, described the regions with the largest pensions pots - Essex, Surrey, Hertfordshire and East Sussex - as a "fairly concentrated part of Southern England" as their pot sizes were "more than double the amount saved by those in Shropshire".
Those in London (£110,775) and the South East (£101,972) reported the biggest single pots on a national basis, almost £43,000 more than people living in Northern Ireland (£67,866).
Partnership said the figures were higher than those recorded by the Association of British Insurers in Q2 2015 as they reflected customers who had used an intermediary such as a financial adviser, and chosen to purchase an annuity on the open market.
The firm added financial advice had a cost attached but could be "extremely beneficial" in choosing the right retirement products.
"Intermediated sales tend to be larger than average as these retirees are prepared to pay for financial advice but it does raise concerns as it suggests that they may have access to better outcomes," Megson said.
"A 65-year-old man with a pot of £125,478 who had common conditions such as high blood pressure, obesity and diabetes could receive £1,050 or 14% more per year by shopping around so it is worth speaking to an adviser."
Top five biggest annuity pots per county:1. Essex - £125,478
2. Surrey - £123,788
3. Hertfordshire - £123,158
4. East Sussex - £121,144
5. Bristol - £120,159
Top five smallest annuity pots per county:
1. Shropshire - £44,336
2. Northumberland - £53,538
3. South Yorkshire - £56,736
4. Devon - £65,687
5. Lincolnshire - £67,158