How much does a 3.00 to 4.99ct H SI1 natural round diamond cost?

As of October 2026, 3.00 to 4.99ct H SI1 natural round diamonds typically cost £23,910 GBP to £58,581 GBP, with a median price of £36,675 GBP. There are currently 311 diamonds matching this specification available across retailers.

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

About 34% of these diamonds are available at multiple retailers, with an average price spread of 29%. A comparison tool like Carat Hunter lets you see all the prices side by side.

3.00 to 4.99ct H SI1 Natural Round

Quick answer

As of October 2026, there are 311 natural round diamonds with H colour and SI1 clarity in the 3.00 to 4.99ct range available across retailers worldwide. Prices typically run £23,910 GBP to £58,581 GBP, with a median of £36,675 GBP. At least 61 retailers stock this exact specification, and 34% of the stones appear at more than one of them, with an average price spread of 29%. Half of all listings fall between £7,638 GBP and £10,247 GBP per carat. The same specification in lab grown form lists at a median of about £376 GBP per carat. Over the last 30 days the median price moved -0.5% and the number of listings moved +2.2%.

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

311

Lowest Price

£11,304 GBP

Highest Price

£106,413 GBP

Average Price

£38,883 GBP

Market Intelligence

Retailers Selling

Cross Retailer %

33.6%

Price Spread

29.4%

30-Day Price Trend

-0.5%

30-Day Supply Change

+2.2%

Volatility (30d)

0.00

Price Range

Price per carat distribution across retailers

$11,881/ct

10th Percentile

$8,684

Median

$11,881

90th Percentile

$15,958

Score Distribution

821 diamonds scored across 4 quality tiers

Excellent

28 (3.4%)

Very Good

179 (21.8%)

Good

160 (19.5%)

Average

454 (55.3%)

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Consider Instead

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

H SI2SI2 inclusions are not visible without magnification

Save 22%

Lab-Grown H SI1Same specifications, lab-grown origin

Save 94%

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