A spokesperson for Robinhood couldn’t immediately be reached for a comment.

Robinhood, which got its start with no-fee brokerage, had said it was starting the savings service on Dec. 13, and payment cards tied to the accounts would begin to ship next month. The Menlo Park, California-based company said it could offer a market-leading interest-rate by investing the money in things like Treasuries and by collecting Mastercard interchange fees—a payment-card levy paid to cardholders’ banks by retailers’ banks.

Investors should always remember one key piece of advice: If something offers a higher interest rate, it’s usually because it’s riskier.

📬 Sign up for the Daily Brief

Our free, fast, and fun briefing on the global economy, delivered every weekday morning.