That includes many low-income families who don't normally file tax returns, people who receive Supplemental Security Income, and some veterans who receive pensions from the federal government.
But it also includes people like wedding photographer Michelle Hans, who is self-employed and whose business has evaporated since the coronavirus shutdowns began.
Like many who are self-employed, Hans usually owes taxes when she files each year. That means the Internal Revenue Service didn't know her bank account number, shutting her out of the first round of payments.
The Pennsylvania resident said she tried numerous times over the past two weeks to use an IRS online tool that allows people like her to input bank account information so that she wouldn't have to wait for a check in the mail. But she had trouble with the site.
'I was dead in the water,' said Hans, who is currently working for the grocery delivery service Shipt.
But after an update was made to the IRS tool last weekend, Hans tried again and successfully transmitted her bank account information, but she still doesn't know exactly when her money will arrive. A scheduled payment date won't likely be available for more than a week, according guidance posted on the IRS website.
Hans is also planning on applying for unemployment benefits this week but isn't expecting an easy process. Pennsylvania wasn't even accepting unemployment applications from self-employed workers until April 18 -- and like other states across the country has had trouble keeping up with the record number of filings.
'I heard there were so many issues with the system that I decided to wait until it was maybe working better,' Hans said.
Who already got their money?
Nearly 90 million of the 150 million eligible for stimulus money had received their payment by April 17, according to the government's latest numbers.
The IRS started by sending money to the people it could reach the fastest. This was anyone who had direct deposit information already on file with the agency because they were due a refund on either their 2018 or 2019 federal tax returns.
But even some people who don't fall into that bucket have already received a paper check in the mail. The IRS began sending those out last week, starting with low-income individuals.
In some cases, families have received money for deceased relatives This can happen when someone has died since filing their 2018 or 2019 tax return. Families are expected to pay back that money, Treasury Secretary Steven Mnuchin told the Wall Street Journal Tuesday.
This week, payments are being delivered to millions of Social Security recipients who don't file tax returns. They can expect the money to automatically arrive however they normally receive their benefits, whether by a check in the mail or direct deposit to their bank account or debit card.
Supplemental Security Income recipients and low-income veterans who receive pensions from the Department of Veterans Affairs -- and who don't file returns -- can expect to see the money in May.
There is one caveat for these groups. If they have children, they're due an actual $500 per dependent. But they won't get this money until next year unless they give dependent information to the IRS. Supplemental Security Income recipients and veterans have until May 5 to input the information online here.
For Social Security recipients, the date has already passed for getting the additional money for dependents. They'll have to file a full return in 2021 to get the additional money.
Others could be waiting for months as the money goes out in phases. The government can process roughly 5 million checks a week.
Some people have told CNN that the money was sent to closed bank accounts -- and that the bank transferred the money back to the IRS. In that case, the payment will likely come later by a check in the mail.
The IRS online tool allows users to input new bank account information -- but only if the agency doesn't already have an account on file from a 2018 or 2019 tax return and hasn't yet processed a stimulus payment.
Filing a 2019 return now is the only way to update direct deposit information that the IRS has on file from a 2018 return. Tax Day was moved from the traditional April 15 to July 15 this year to give filers more time.
Then, there are millions of low-income people who are not normally required to file tax returns that will have to take some action before receiving their stimulus money.
Generally, these are individuals who did not earn more than $12,200 last year or married couples who did not earn more than $24,400.
But they won't have to file a whole new form, as earlier guidance from the IRS suggested. Instead, it created an online tool for non-filers that asks for basic information including names, dates of birth, and Social Security numbers for the person filing and his or her dependents. They won't have to provide any income information.
The tool allows you to input bank account information for a direct deposit, or an address to receive a paper check.
Who's not eligible?
Eligibility is largely based on income, and it excludes individuals earning more than $99,000, head of household filers with one child who earn more than $136,500, and married couples without children earning more than $198,000.
Families earning a little more may still be eligible if they have children. The phase-out limit depends on how many children they have. For a typical family of four, the amount is completely phased out for those with incomes exceeding $218,000.
Those who can be claimed as a dependent for tax purposes, like many college students, are also ineligible for the payments, as well as undocumented immigrants who don't have Social Security numbers.