How much does a 1.00 to 1.49ct F SI1 natural round diamond cost?

As of October 2026, 1.00 to 1.49ct F SI1 natural round diamonds typically cost £1,821 GBP to £5,240 GBP, with a median price of £2,944 GBP. There are currently 3,177 diamonds matching this specification available across retailers.

Where can I find the best price on a F SI1 round diamond?

About 35% of these diamonds are available at multiple retailers, with an average price spread of 52%. A comparison tool like Carat Hunter lets you see all the prices side by side.

1.00 to 1.49ct F SI1 Natural Round

Quick answer

As of October 2026, there are 3,177 natural round diamonds with F colour and SI1 clarity in the 1.00 to 1.49ct range available across retailers worldwide. Prices typically run £1,821 GBP to £5,240 GBP, with a median of £2,944 GBP. At least 68 retailers stock this exact specification, and 35% of the stones appear at more than one of them, with an average price spread of 52%. Half of all listings fall between £2,071 GBP and £3,373 GBP per carat. The same specification in lab grown form lists at a median of about £308 GBP per carat. Over the last 30 days the median price moved -0.8% and the number of listings moved +6.3%.

Three of the best scored stones at this specification right now:

Caratlytics Diamond Price Index, September 2026: natural diamonds at 2,335 USD per carat and lab-grown at 443 USD per carat, a natural to lab ratio of 5.3 to 1. Round natural stones in the index: 2,248 USD per carat, +7.6% month on month. See the full index release

Figures come from current listings across more than 100 retailers and refresh daily. The index is a monthly release.

Last updated: October 2026

Available

3,177

Lowest Price

£965 GBP

Highest Price

£10,668 GBP

Average Price

£3,303 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

34.6%

Price Spread

52.0%

30-Day Price Trend

-0.8%

30-Day Supply Change

+6.3%

Volatility (30d)

0.00

Price Range

Price per carat distribution across retailers

$3,355/ct

10th Percentile

$2,358

Median

$3,355

90th Percentile

$5,767

Score Distribution

6.5K diamonds scored across 4 quality tiers

Excellent

771 (11.9%)

Very Good

1,521 (23.4%)

Good

1,634 (25.2%)

Average

2,569 (39.6%)

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Consider Instead

Save money without compromising on what matters. These alternatives are visually similar but cost less.

F SI2SI2 inclusions are not visible without magnification

Save 22%

Lab-Grown F SI1Same specifications, lab-grown origin

Save 89%

Related Specifications

D IF D VVS1 D VVS2 D VS1 D VS2 D SI1 E IF E VVS1 E VVS2 E VS1 E VS2 E SI1 F IF F VVS1 F VVS2 F VS1 F VS2 F SI1 G IF G VVS1 G VVS2 G VS1 G VS2 G SI1 H IF H VVS1 H VVS2 H VS1 H VS2 H SI1 I IF I VVS1 I VVS2 I VS1 I VS2 I SI1