Today we’re introducing two new investment options to Mercury Treasury: MCRYX, an ultra-short bond fund built with Morgan Stanley Investment Management, and MRGXX, a government money market fund share class built with State Street Investment Management. MCRYX is live now, and MRGXX arrives next week. These products replace our previous offerings, and you won’t find them anywhere else. They’re designed to help you pursue higher net yields than our previous Treasury offerings without adding credit risk or extending duration.
The tradeoff we wanted to eliminate
If you’re running a company with real money in the bank, whether from a raise or from revenue, that cash has a job to do. It needs to stay safe, stay liquid, and, ideally, earn something while it waits. The trouble is that most of the market asks you to pick two of the three. Cash Management platforms typically compete on headline yield, and the fastest way for them to quote a higher potential yield is to offer riskier funds or assets. For you, the alternative is opening accounts across multiple platforms to chase extra basis points, which fragments the cash you worked hard to consolidate and adds one more login for your finance team to babysit.
That tradeoff exists because most platforms offer the same commoditized mutual funds. When everyone offers identical funds and share classes, more risk becomes the only lever left.
MCRYX, built with Morgan Stanley Investment Management
MCRYX is a new ultra-short bond fund, created through our long-standing partnership with Morgan Stanley Investment Management. It follows the same conservative investment strategy as the fund it replaces, so nothing about the risk profile changes. Your money stays in high-quality, short-duration assets. MCRYX is live today and yields up to 3.88% through Mercury Treasury, with 1-2 day liquidity.
MRGXX, built with State Street Investment Management
MRGXX is a new government money market fund share class developed with State Street Investment Management, arriving next week. It invests across treasury debt, government agency debt, and repurchase agreements, which gives the fund flexibility to seek value across the full range of government-backed assets. It carries a lower expense ratio than the fund it replaces, maintains a stable $1 net asset value with top stability ratings from S&P and Moody’s, and offers same-day liquidity.
State Street Investment Management manages nearly $650B in cash globally — their core competency — with $6.3T in AUM based on 2Q 2026 earnings reports. Their parent company, State Street Bank, is the second-oldest bank in the U.S. and a Global Systemically Important Bank (GSIB).
Yield, responsibly delivered
The new offerings reflect a standard we hold ourselves to: seeking higher returns should come from stronger partnerships, never from adding risk. These are not BBB-rated bonds, mortgage-backed securities, or longer duration securities within a mutual fund wrapper. Moreover, Mercury Treasury is managed by Mercury Advisory, our SEC-registered investment adviser with a legal fiduciary duty of care and loyalty to clients. Not only is this standard core to our philosophy, but when we evaluate a fund, we’re obligated to act in your interest.
Treasury, where you already bank
Your Treasury portfolio lives alongside your checking accounts, cards, bill pay, and spend management, so your idle cash works harder without leaving the platform where you already run your finances. Auto-transfer rules can move money to and from Treasury automatically as balances change. Positions sync with QuickBooks, Xero, and NetSuite. There’s no new account to open and no separate login — just your full financial picture in one place.
Already a Treasury customer? You’re set.
If you previously invested with Mercury Treasury, your holdings will migrate automatically. MULSX holders moved to MCRYX on July 17, and JTCXX holders will move to MRGXX on August 21. Full migration details and disclosures can be found in our Help Center.
What’s next
Later this year, Treasury Ladders will let you structure cash across U.S. Treasury securities with longer maturities and plan around future needs with more precision. It’s the next step in the same direction: giving ambitious companies institutional-grade tools inside the platform they already trust.
If your company holds $250,000 or more across Mercury accounts, you can apply for Mercury Treasury today. If you’re already a Treasury customer, you’ll see both funds in your portfolio soon. You can read the full announcement with Morgan Stanley Investment Management and State Street Investment Management in our press release.
