Third party analysis for a 3,350 nmi transatlantic flight show the 787-9 has a slight advantage over the A330-900neo in cash cost per available seat miles, while the Airbus outperforms the Boeing once capital costs are included, based on the A330-900neo cost an estimated $10.6m less.

They have close economics but the A330neo costs up to $30m less, according to another publication.

An A330-900 is worth $115 million in 2018, while a new B787-9 valuation is $145 million, up from $135 million in 2014, but it may have been sold for $110–15 million to prevent A330neo sales.

Between the 2004 launch of the Dreamliner and the A330neo launch in 2014, the market was split almost equally between both, with between 900 and 920 A330ceos sold against 950 to 1,000 787-8/9s.

Between 2014 and the neo first flight in October 2017, the A330/A330neo had 440 orders (excluding freighters) compared to 272 for the 787-8/9 (excluding the -10), or since the 787 launch, 1211 A330ceo/neos compared to 1106 787-8/9s.

Teal Group's Richard Aboulafia believes that the A330neo should dominate the lower range and lower capacity end of the twin aisle market because the 787-8 has the high operating economics and unit price associated with its 8,000-nm range.

Flightglobal Ascend Consultancy forecasts 600 deliveries including 10% of -800 variants, less optimistic than Airbus' 1,000.

At entry into service in 2018, sales were disappointing and A330 production was to be cut to 50 in 2019 down from 67 in 2017: while it is the widebody with the largest operator base with 1,390 deliveries since 1993, the fleet is still very young with only 46 aircraft retired.
Airbus believed A330 operators would start fleet renewal beginning in 2020.
With the exception of Delta, industry-leading airlines preferred the Boeing 787.

Between January 2014 and November 2019, the A330/A330neo had 477 net orders (net of cancellations) compared to a total of 407 for all three variants of the 787.
The A330neo program was the best-selling Airbus widebody over the same period.

Airbus believes there is potential for the A330neo in the growing long-haul, low-cost carrier sector.
While Airbus expected a market for over 1,000 A330neos, one pessimistic forecast reported in 2018 came in as low as 400 sales, in that the A330neo was late to the market and fuel prices had declined markedly over the years, reducing demand.
19% of A330 operators are already 787 customers though some A330 operators have been dual sourcing from both Boeing and Airbus.
Leeham News, on the one hand considered the A330-800 does not really cover the upper end of New Midsize Airplane studied by Boeing for some years, on the other hand stated that the A330-800 provides Airbus a cost-effective entry to the upper end of the middle of the market.
In May 2019, Airbus's chief commercial officer made clear the company has a “rock”, the A321neo, and a “hard place”, the A330-800, for any airframer intending to bring a new airplane into the middle of the market at a time when Boeing was mired in the 737 MAX crisis.

Compared to a 283-seat, 9-abreast 787-9, Airbus claims a 1% lower fuel burn for the -900: 3% higher due to the 4–5 t (8,800–11,000 lb) higher OEW, but 4% lower due to the 4 m (13 ft) wider wingspan, and 3% lower fuel burn per seat in a 287-seat, 8-abreast configuration, reaching 7% with a 303-seat, 9-abreast layout.
Third party analysis for a 3,350 nmi transatlantic flight show the 787-9 has a slight advantage over the A330-900neo in cash cost per available seat miles, while the Airbus outperforms the Boeing once capital costs are included, based on the A330-900neo cost an estimated $10.6m less.
They have close economics but the A330neo costs up to $30m less, according to another publication.
An A330-900 is worth $115 million in 2018, while a new B787-9 valuation is $145 million, up from $135 million in 2014, but it may have been sold for $110–15 million to prevent A330neo sales.
Between the 2004 launch of the Dreamliner and the A330neo launch in 2014, the market was split almost equally between both, with between 900 and 920 A330ceos sold against 950 to 1,000 787-8/9s.
Between 2014 and the neo first flight in October 2017, the A330/A330neo had 440 orders (excluding freighters) compared to 272 for the 787-8/9 (excluding the -10), or since the 787 launch, 1211 A330ceo/neos compared to 1106 787-8/9s.
Teal Group's Richard Aboulafia believes that the A330neo should dominate the lower range and lower capacity end of the twin aisle market because the 787-8 has the high operating economics and unit price associated with its 8,000-nm range.
Flightglobal Ascend Consultancy forecasts 600 deliveries including 10% of -800 variants, less optimistic than Airbus' 1,000.
At entry into service in 2018, sales were disappointing and A330 production was to be cut to 50 in 2019 down from 67 in 2017: while it is the widebody with the largest operator base with 1,390 deliveries since 1993, the fleet is still very young with only 46 aircraft retired. Airbus believed A330 operators would start fleet renewal beginning in 2020. With the exception of Delta, industry-leading airlines preferred the Boeing 787. 
Between January 2014 and November 2019, the A330/A330neo had 477 net orders (net of cancellations) compared to a total of 407 for all three variants of the 787. The A330neo program was the best-selling Airbus widebody over the same period.
Airbus believes there is potential for the A330neo in the growing long-haul, low-cost carrier sector. While Airbus expected a market for over 1,000 A330neos, one pessimistic forecast reported in 2018 came in as low as 400 sales, in that the A330neo was late to the market and fuel prices had declined markedly over the years, reducing demand. 19% of A330 operators are already 787 customers though some A330 operators have been dual sourcing from both Boeing and Airbus. Leeham News, on the one hand considered the A330-800 does not really cover the upper end of New Midsize Airplane studied by Boeing for some years, on the other hand stated that the A330-800 provides Airbus a cost-effective entry to the upper end of the middle of the market. In May 2019, Airbus's chief commercial officer made clear the company has a “rock”, the A321neo, and a “hard place”, the A330-800, for any airframer intending to bring a new airplane into the middle of the market at a time when Boeing was mired in the 737 MAX crisis.
Compared to a 283-seat, 9-abreast 787-9, Airbus claims a 1% lower fuel burn for the -900: 3% higher due to the 4–5 t (8,800–11,000 lb) higher OEW, but 4% lower due to the 4 m (13 ft) wider wingspan, and 3% lower fuel burn per seat in a 287-seat, 8-abreast configuration, reaching 7% with a 303-seat, 9-abreast layout.
Airbus A330neo