WASHINGTON (AP) — Under criticism after weeks of shortages, President Joe Biden’s administration is working to make COVID-19 rapid test kits more available and accessible to Americans by boosting supply and lowering costs. A new federal website to request free test kits officially launches Wednesday — but was available to use Tuesday — with the first shipments going out to Americans by the end of the month. In addition, most Americans are now able to seek reimbursement for tests they purchase.

Key details about the new programs:

HOW CAN I REQUEST A FREE TEST?

Free tests can be ordered at covidtests.gov or at usps.com/covidtest. The first tests will ship by the end of January. The White House says “tests will typically ship within 7-12 days of ordering” through the U.S. Postal Service. USPS reports shipping times of one-three days for its first-class package service in the continental United States. Shipments to Alaska, Hawaii, Army Post Office (APO), Fleet Post Office (FPO) and Diplomatic Post Office (DPO) addresses will be sent through Priority Mail.

Importantly, given the shipping and process times, Americans will need to request the tests well before they meet federal guidelines for requiring a test.

DOES THE WEBSITE WORK?

The White House emphasized that the website was in “beta testing” when it made tests available for ordering for the first time Tuesday. At points, more than 750,000 people were accessing the website at the same time, according to public government tracking data, but it was not immediately known how many orders were placed.

There were isolated reports Tuesday afternoon of issues relating to the website’s address verification tool erroneously enforcing the four-per-household cap on apartment buildings and other multi-unit dwellings, but it was not immediately clear how widespread the issue was.

WHEN SHOULD I TEST?

The Centers for Disease Control and Prevention recommends at-home testing when people experience COVID-19 systems including fever, cough, sore throat, respiratory symptoms and muscle aches; five days after a potential COVID-19 exposure; or as part of test-to-stay protocols in schools and workplaces.

HOW MANY TESTS CAN I ORDER FROM THE WEBSITE?

The White House says that “to promote broad access,” shipments from covidtests.gov will initially be limited to four rapid tests per residential address, no matter the number of occupants.

IS THERE ANOTHER WAY TO GET A TEST KIT FOR FREE?

As of last Saturday, private insurers have been required to cover the cost of up to eight at-home rapid tests per month per insured person, under a new Biden administration rule.

People have the option of buying tests at a store or online, then seeking reimbursement from their health insurance provider. Insurers are being incentivized to work with pharmacies and retailers to develop plans to cover the cost of the tests with no out-of-pocket cost to customers, but those programs will not be immediately widespread.

Those with public health insurance through Medicare, or without insurance, are being directed to covidtests.gov to order tests or to community health centers in their area offering free testing.

HOW WILL I BE REIMBURSED?

The Biden administration says the procedures will differ from insurer to insurer, and it is encouraging Americans to save receipts from rapid test purchases for later reimbursement and to reach out to their insurance providers for information.

The requirement only covers purchases on or after Jan. 15. Insurers are not expected to retroactively reimburse the cost of tests purchased earlier.

WHAT ARE OTHER TESTING OPTIONS?

The Biden administration is emphasizing that the website is just one tool for Americans to access COVID-19 testing. Millions of free tests are available at participating pharmacy locations, community health centers and Federal Emergency Management Agency-backed sites in some parts of the country experiencing a surge in cases.

WHICH HOME TEST WILL I GET?

That will vary. The federal government has secured more than 420 million tests for distribution through covidtests.gov already, with plans to increase the order to 1 billion tests in the coming weeks. All of the tests supplied will be authorized by the Food and Drug Administration and are capable of detecting the more-transmissible omicron variant of COVID-19, which is the dominant strain in the U.S. While they are packaged differently and may use slightly different procedures, officials said, the test mechanisms of detection and effectiveness are generally the same. All tests will come with detailed instructions.

WHY IS BIDEN BUYING THESE TEST KITS?

It represents an acknowledgement by the president that the administration needs to do more to increase access to COVID-19 testing, which is an important tool to help slow the spread of the coronavirus.

Since in some cases infected people may not show symptoms, testing is the only way to find out if they have the virus so they can avoid being out and about and potentially spreading disease.

Demand for test kits soared as the holidays neared and people grew eager to test themselves and their families before traveling and as the omicron variant spread rapidly in just a few weeks to become the dominant strain in the U.S.

Biden’s promise of 1 billion test kits is in addition to the administration’s earlier pledge to send 50 million rapid tests to community health centers across the country.

HOW MUCH WILL THE PROGRAM COST?

The White House estimates the cost of purchasing and distributing the first 500 million tests at about $4 billion. That will be paid for with money from the $1.9 trillion coronavirus relief bill Biden signed into law in March.

WILL THE GOVERNMENT PROGRAM MAKE IT HARDER FOR ME TO FIND A TEST AT THE DRUGSTORE?

White House officials say the covidtests.gov tests are coming from new manufacturing capacity and should not interfere with existing supplies on which drugstores, health clinics and state governments are relying.