The tax day deadline may have come and gone, but unfortunately, there are still millions of Americans who are waiting patiently for their refund checks.

In fact, according to Time magazine, “if you’re in the roughly 10 percent of 160 million Americans taxpayers whose filings are even remotely complicated,” you could face a manual review that could potentially stretch well into the second half of the year or even 2023.

In all, roughly sixteen million households could be affected by delays in getting their hands on the cash that they are already entitled to.

“There are simple steps that people can take that will help them navigate this challenging tax season,” Internal Revenue Service (IRS) Commissioner Chuck Rettig said in a statement.

“Filing electronically and using online resources instead of calling are just some of the steps that can help people avoid delays,” he continued.

The IRS, however, has come through for most American taxpayers this tax season. It confirmed that about nine out of ten refunds have arrived within three weeks this year. As of April 15, per the agency’s data release, it has issued more than seventy-eight million refunds worth more than $242 billion. Broken down, the average refund comes in at $3,103, a hefty 8 percent increase compared to last year.

Overall, according to CNBC, the IRS has received 118 million electronic returns, which make up about 96 percent of all filings. That number, however, may change as more tax returns are filed before the extension deadline on October 17.

The biggest culprit leading to refund delays is undoubtedly paper returns, which most tax experts agree will only add to the massive backlog of unprocessed returns and correspondence at the agency.

National Taxpayer Advocate Erin Collins recently told a House committee that paper returns remain “at the heart of the agency's challenges and processing tax returns.” Collins even called them the IRS’ “kryptonite,” as many paper returns must be manually entered into the system.

While it may take twenty-one days to process error-free electronic filings, refunds for paper returns may take “six months longer,” Collins explained.

Meanwhile, in a recent interview on National Public Radio, the Treasury Department’s Deputy Secretary, Wally Adeyemo, contended that the agency needs more financial support from Congress to enforce existing tax laws and improve the tax filing experience for all Americans, adding that “the most important thing that we need to do is to improve the technology of the IRS.”

President Joe Biden has been pushing for an $80 billion investment over the next decade to rebuild the tax agency’s capabilities, but that ambitious House-approved effort has stalled out in the Senate.

Ethen Kim Lieser is a Washington state-based Finance and Tech Editor who has held posts at Google, The Korea Herald, Lincoln Journal Star, AsianWeek, and Arirang TV. Follow or contact him on LinkedIn.

Image: Reuters.