How long the Federal Reserve will keep rates high is uncertain, but select banks continue to boost yields on an array of products to attract savers’ dollars. To that end, Sallie Mae recently pushed the annual percentage yield on its one-year certificate of deposit to 5.5%, an increase of 40 basis points. A basis point is equal to one one-hundredth of a percent. Other institutions that have pushed rates higher as of late include Marcus by Goldman Sachs and Synchrony Financial , where one-year CDs pay yields of 5% and 5.1%, respectively. The Fed’s series of 11 rate hikes dating to March 2022 have helped lift yields on these investments, as well as on Treasurys. Analysts think these sweetened yields have higher to go at least for now. “We expect more rate action in the weeks ahead,” wrote Michael Kaye, analyst at Wells Fargo in a Friday report on deposit trends. CD rates are also higher among online institutions offering 2-year instruments. Marcus and Synchrony each hiked yields by 5 basis points to 4.4% and 4.35%, respectively. CDs offer the benefit of luring “sticky” deposits to banks, as customers face a penalty if they try to withdraw their money from these instruments before their maturity. However, customers who’ve already snapped up a CD are effectively locked into that rate for that stated term. That’s different from a high-yield savings account, wherein the bank can change the rate at any time. The question for investors is how much longer will these banks sweeten their yields. Morgan Stanley analyst Betsy Graseck said in a Monday report that “history suggests that deposit costs only peak 1 to 2 quarters after the Fed starts cutting.” “Even though the market doesn’t expect any more rate hikes this cycle, we expect deposit costs to keep rising until the Fed cuts rates,” she said. — CNBC’s Michael Bloom contributed to this story.