“We believe what we’re doing is very consistent with their mission,” Roth said last month in a telephone interview.

Annaly, the largest mortgage REIT with $82 billion of assets, last quarter had an insurance subsidiary join the Des Moines bank. The New York-based REIT will use the loans “as one of the many complementary funding alternatives available” to the company, President Kevin Keyes said in an e-mail. “The FHLBs are very strict with respect to their credit process and criteria for access to advances.”

Invesco Mortgage Capital’s unit joined an FHLB last quarter and started borrowing against its AA rated commercial-mortgage securities, Chief Executive Officer Richard King said on a conference call last month. The Atlanta-based firm in the future may use the membership for residential and commercial mortgages, he said.

Ladder Capital uses its FHLB funding from Indianapolis to buy mostly AAA rated bonds, CEO Brian Harris said last month in a conference call. The New York-based firm is in the process of applying to increase the $1.4 billion in available financing from the FHLB, Chief Financial Officer Marc Fox said on the call.

REITs Diversifying

Hatteras Financial Corp. and Redwood Trust Inc. are among other mortgage REITs considering FHLB memberships, their executives said on conference calls in the last two months. Spokesmen for Invesco Mortgage, Ladder Capital, Hatteras and Redwood declined to comment.

The REITs are diversifying their investments and funding sources after struggling to navigate the Federal Reserve’s moves to scale back its monthly bond buying, as well as facing dwindling returns on distressed debt. The FHLBs offer a better way to finance some of their new investments since the market for home loan bonds is stagnating, with issuance down 73 percent in 2014, according to data compiled by Bloomberg.

Some FHLBs aren’t ready to start lending to the mortgage REIT units. The Home Loan Bank of Atlanta is still weighing it, in part because of regulators’ concerns, Robert F. Dozier Jr., its chief business officer, said last month in an interview.

Expanding Banks

“We’re taking a methodical approach,” he said.