CMC Markets Opens the Overnight US Session to Fractional Share Orders

CMC Markets has extended round-the-clock US share dealing to its retail investing platform, CMC Invest, opening the full 24/5 window to fractional orders as well as whole shares, the London-listed broker said on Thursday. Fractional trades run in the same session as standard tickets.

Orders placed in the extended and overnight sessions will accept every order type the platform offers, market orders included. In July, CMC widened its 24/5 book to more than 5,000 US shares and ETFs but gave CMC Invest only pre- and post-market dealing. The practical effect for a UK client is that a small US share order can be filled outside New York hours at the price on screen, rather than sitting as an instruction that may never trigger.

That pairing — fractional tickets plus unrestricted order types during overnight hours — is unusual among retail brokers selling US overnight access. Robinhood launched its retail overnight session in 2023 with a 24-hour market covering 43 stocks and ETFs on limit orders only, and its client documentation still restricts that window to whole-share limit orders and excludes fractional ones. The constraint is largely a venue issue: Blue Ocean ATS, which handles the bulk of US overnight volume, accepts limit orders valid for that session alone, a rule brokers routing through it inherit. Interactive Brokers sends about 10,000 US stocks and ETFs into the 8 p.m. to 3:50 a.m. ET window through its own venue, with Blue Ocean liquidity behind it.

Fractional Launch and Pricing

The other half of the announcement is newer than the trading hours. CMC introduced fractional shares and ETFs on its UK platform in July, starting from GBP 1, across ISAs, SIPPs and general investment accounts. That launch also scrapped commission on UK and European share CFDs, narrowing the pricing gap between investing and leveraged trading inside the same account. Lachlan Rourke-Davies, senior product manager at CMC Markets, said the combination lets clients "invest the amount that works for them."

Longer US hours have been spreading across the UK market for a year, leaving the fractional ticket and open order types as the parts of the announcement not already available elsewhere. IG put 110 US stocks on a schedule running from 1 a.m. Monday to 10 p.m. Friday in September 2025, across its investing and leveraged accounts, up from a 16-hour day. Charles Schwab has since moved more than 1,100 securities, including S&P 500 and Nasdaq-100 names, onto a 24/5 schedule for all its US retail clients. Laurence Booth, global head of markets at CMC Markets, said "US markets don't stop moving when the core session closes."

CMC Invest advertises no dealing commission on any of its three plans, but currency conversion carries a spread of up to 0.99% on the entry-level Core plan, 0.50% on Plus and 0.39% on Premium, according to its published fee schedule. The two paid tiers also charge monthly subscriptions of up to GBP 6.99 and GBP 10.99. Buying a slice of a US share overnight crosses the same spread as a whole share.

CMC Invest launched in 2022 to broaden group revenue beyond contracts for difference. The parent reported pre-tax profit of GBP 101.3 million for the year to 31 March 2026, up 20%, on net operating income of GBP 392.6 million, with guidance for the current year higher again.