A property near Royal Ascot would set the average homebuyer back £4,263 per month in mortgage payments, data from Alexander Hall found.
This is based on an average house price of £889,503 in the SL5 postcode, with a 15% deposit of £133,425.
However, the monthly cost for a royal residence is much higher.
Alexander Hall looked at eight royal properties, including Buckingham Palace and Clarence House, to estimate their current market values and what the monthly mortgage payments would be.
Buckingham Palace topped the list, with an estimated value just under £4bn and a monthly mortgage payment of £19m after a 15% deposit of £596m.
Hampton Court Palace came in at £1.038bn, needing a £155.6m deposit and £4.9m monthly payment.
St James’s Palace was valued at £623.8m, with a £93.6m deposit and £2.9m each month.
Meanwhile, Windsor Castle had a value of £594m, a deposit of £89.1m and monthly payments of £2.8m.
Kensington Palace was valued at £465.2m, requiring a £69.8m deposit and £2.2m each month.
The figures were lower for Clarence House at £68.4m, with a £10.3m deposit and a monthly payment of £327,796.
Balmoral was put at £62.4m, needing a £9.4m deposit and £299,135 a month.
Sandringham was the lowest, at £55m, with an £8.3m deposit and £263,980 each month.
Stephanie Daley, director of partnerships at Alexander Hall, said: “We may have seen mortgage market affordability improve in recent months but you’re still going to need extremely deep pockets if you want to keep up with your monthly payments on a royal residence.
“Much like the wider property market itself, the royal property portfolio does vary quite drastically when it comes to estimated market values and the potential mortgage payments required – from £19m per month for Buckingham Palace to a comparatively palatable £264,000 per month for Sandringham.
“Whilst it’s highly unlikely that these royal properties will ever hit the open market, engaging a highly experienced mortgage adviser is the best way to ensure you secure the perfect mortgage product to suit your individual needs, even if you are a high-net-worth with your eyes on Buckingham Palace.”
