AMSTERDAM, Jan 15 (Reuters) - Shares of ASML ASML.AS, the world's biggest maker of equipment used to manufacture computer chips, hit new all-time high on Thursday after top customer TSMC 2330.TW announced larger than expected capital spending plans to keep up with booming demand for artificial intelligence chips.

TSMC hiked its planned capital spending to between $52 billion and $56 billion in 2026, blowing past market expectations of $46 billion according to analysts polled by Visible Alpha. That means up to 21% more money that could be used to buy chipmaking equipment.

The news pushed ASML's shares 4.3% higher by 0952 GMT, totalling a rise of 23% in January alone and surpassing $500 billion in market capitalisation for the first time, extending its lead as Europe's most valuable company.

Analysts have said ASML is a clear beneficiary of the AI boom, which has led to expansion plans by many chipmakers, notably South Korea's Samsung 005930.KS and SK Hynix 000660.KS, which make memory chips used in AI technology, and now TSMC, the main manufacturer of chips for Nvidia NVDA.O and Apple AAPL.O.

"The new plan is great for equipment vendors in 2026, it will lead to consensus estimates upgrades across the board," analyst Michael Roeg from Degroof Petercam said about TSMC's announcement.

ASML, which is due to report fourth-quarter earnings on January 28, has so far forecast only tepid growth for 2026 or flat sales at worst.