* Property sales, investment fall at double-digit pace

* Property slowdown remains drag on economic growth

BEIJING, Oct 18 (Reuters) - China's property sales and investment posted double-digit declines as efforts to support big cities failed to bolster confidence in an industry struggling to emerged from crisis, although the pace of contraction slowed.

Property sales by floor area fell 19.77% year-on-year, narrowing from a 23.95% fall in August, according to Reuters calculations based on data released on Wednesday by the National Bureau of Statistics (NBS).

In September, home sales were 64.73 million square metres lower than in September 2019, the highest in three months, showing a deepening sector correction disrupted by COVID-19 and a government crackdown on debt.

The property sector is struggling to regain its footing, with piecemeal support measures providing just a short-lived boost in tier-one cities, while the rest of the country grapples with an oversupply of homes and low confidence.

The data comes just hours ahead of a deadline for Country Garden Holdings, China's biggest private property developer, to make a coupon payment to its bond investors or risk defaulting on its $11 billion in overseas debt, which would deepen the country's real estate crisis.

Separate data on Wednesday showed China's economy grew at a faster-than-expected clip in the third quarter, while domestic consumption also picked up pace last month, suggesting the recent recovery may carry enough steam to reach Beijing's full-year growth target.

However, the prolonged debt crisis in the property sector, which accounts for nearly a quarter of economic output, has been a drag on China's growth this year, hampering activity across a broad swathe of industries.

The International Monetary Fund downgraded its 2023 and 2024 growth forecasts for China, saying the property slowdown could cause China's GDP to decline, according to a report released on Wednesday.

"The property weakness needs to be monitored which requires more policy support. Further relaxation of property curbs can be expected but the effects might take a bit longer time to materialise," said Zhou Hao, Economist at Guotai Junan International.

Property investment fell 18.7% from a year earlier after a 19.1% drop in August, according to Reuters calculations.

"S&P Global Ratings expects that the low number of construction starts, an inventory overhang in lower-tier cities, and ever-tightening escrow restrictions will keep property sales depressed," S&P's credit analysts said in a note on Monday.

The credit rating agency expected 2024 sales to drop by another 5%.

Property sales by floor area in China fell at a faster pace in January-September compared with a year earlier, down 7.5% versus a 7.1% fall in the first eight months of 2023.

Property investment in the first nine months of 2023 fell by 9.1% from a year earlier, after slumping 8.8% in January-August, according to NBS data.

New construction starts measured by floor area fell 23.4% year-on-year, after a 24.4% drop in the first eight months.

Funds raised by China's property developers were down 13.5% year-on-year after a 12.9% slide in January-August.

(Reporting by Liangping Gao, Ella Cao and Ryan Woo; Editing by Christian Schmollinger and Sam Holmes)