The honest answer is what you can comfortably afford without feeling stretched. The old 'three months salary' rule was invented by De Beers in the 1930s as marketing and has no real basis. In the UK today, the average spend on an engagement ring is around £2,000 to £4,000, but plenty of rings cost less and plenty cost more. With a lab grown diamond, the same budget goes much further: a £2,500 budget that buys a 0.5 carat mined diamond ring can comfortably buy a 1 carat lab grown ring of similar grade. Start with the budget that feels right to you, then choose the largest stone, best metal and setting that fits within it. The ring should suit her hand and her style, not match a guideline pulled from a magazine.
Browse our engagement ring collection to see what your budget buys in lab grown. A solitaire setting such as the Amaris starts at 550 pounds, and you can compare by shape in our round engagement rings.
What the average really means
The £2,000 to £4,000 figure is the UK retail average, not a target. Some couples spend £800 and are delighted. Others stretch to £8,000 for a piece they want to inherit. Neither is wrong. The right number is what does not put financial stress on the months after the engagement.
Where lab grown changes the maths
For the same budget, lab grown diamonds give you roughly twice the carat at the same quality grade, or the same carat at a higher colour and clarity. A £2,000 budget that historically bought a small mined stone now buys a meaningfully larger, brighter lab grown one. This is the single biggest shift in engagement ring buying in the last decade.
What a Luma ring actually costs
Averages are useful for context but they do not tell you what you will pay. Here are our own numbers. A 1ct IGI certified lab grown diamond in a plain 18k white gold solitaire comes to around £1,350 to £1,400. The same ring with a 2ct stone is around £1,500 to £1,550. Our lowest priced complete engagement ring starts from around £820, with a 0.5ct stone.
The figure worth sitting with is the gap between those first two. Going from a 1ct centre stone to a 2ct adds about £150 to the ring, not double the price. With a mined diamond, that same step would multiply the cost of the stone several times over. Prices move a little with the individual diamond and with the metal, so treat these as typical rather than fixed.
Related questions
Is the three months salary rule a real thing?
No. It was a De Beers marketing slogan from 1938 to drive sales. It has no basis in tradition and no place in modern financial advice.
What does a 1 carat lab grown engagement ring cost at Luma?
Around £1,350 to £1,400 for a 1ct IGI certified stone in a plain 18k white gold solitaire. A 2ct version of the same ring is around £1,500 to £1,550. We make in Hatton Garden and sell direct, so there is no retail markup between the workshop and the price you see.
What is the most popular engagement ring price in the UK?
Roughly £2,500 to £3,500 covers the largest share of UK engagement ring purchases. Above £5,000 is the higher end. Below £1,500 is the entry level.
Can you finance an engagement ring at Luma?
Yes. Klarna is available at checkout for interest free instalments or longer term financing.
If you want to see how far a set budget stretches in lab grown, read our guide to lab grown engagement rings under 2,000 pounds, or book a consultation at our Hatton Garden studio and we will build to your number.