Starting Saturday at 6 a.m., the first phase of D.C. Mayor Muriel Bowser’s vaccine mandate goes into effect, requiring bars, restaurants, gyms, and other businesses to ask patrons age 12 or older for proof of vaccination.

At first, guests will only need to show that they’ve received at least one dose of a vaccine. Starting on Feb. 15, two doses of a shot will be required for entry. Currently there is no phase that would require a booster – although some local businesses have independently decided to require boosters for entry.

Bowser announced the mandate in late December as omicron tore through the region, saying it was intended to encourage more D.C. residents to get vaccinated.

“We do know that mandates have the ability to move people who are not vaccinated to become vaccinated,” Bowser said.

Here’s what you need to know before heading out this weekend:

What businesses are requiring proof of vaccination? 

The city has a posted list of establishments that will be asking for proof of vaccination. These include indoor restaurants, nightclubs, bars, movie theaters, concert and theater venues, and gyms.

Certain meeting spaces — like hotel common rooms, convention centers, or facilities hosting events — are also required to ask for proof of vaccination. Expect to be asked for proof upon entry to one of these businesses.

You won’t need to show proof of vaccination to stay in a D.C. hotel, per the mandate, but you will need to show proof of vaccination to use the hotel’s common space, fitness facilities, or its bar or restaurant. Some hotels may choose to require vaccination, independently of the city’s mandate.

Basically, if you are going to some place that involves sitting down indoors for an extended period of time, that place is likely included in the mandate — although with some caveats.

Where won’t I have to show proof of vaccination?

Museums, houses of worship, grocery stores, and retail stores are all exempt from the mandate. As Fritz Hahn of the Washington Post put it, any place where you’ll be walking around during your visit won’t require proof of vaccination. However, some of these kinds of businesses and establishments have put their own vaccine mandates in place — check before you go.

There is an exception to this, however, if a store, bar, or church holds an event that involves sitting indoors for a period of time, like a reading or a concert. If a house of worship, for example, is rented out for a non-religious event like a performance or presentation, guests would be required to show proof of vaccination.

What if I’m quickly stopping in a business to pick up fast food or a takeout order? 

This is sticky. According to DC Health’s FAQ sheet, you are exempt from showing proof of vaccination if you’re only “briefly entering” a business, say, to use the bathroom or grab an order to-go. However, the enforcement for fast-food or fast-casual spots that offer both to-go and dine-in service (think: Taco Bell Cantina) is murky.

Unlike a restaurant, a host doesn’t greet you when you walk into Taco Bell Cantina, and sometimes it’s unclear whether people are dining in or taking out. Businesses are required to post signage outside indicating they require proof of vaccination — potentially sowing more confusion for passers-by who just plan to pop in.

Food halls are another gray area of the vaccine mandate. Vaccines won’t be required unless you’re sitting down and dining. According to the Washington Post, individual vendors at Union Market will ask you if you are dining in or taking items to-go. If you’re dining, you will need to show proof of vaccination and receive a card that’s displayed at your table.

What can I show as proof of vaccination? 

You have several options. Acceptable forms of vaccination proof include your physical card issued from the Centers for Disease Control and Prevention (CDC), a photocopy of that card, or a photograph of that card. You can also show proof of vaccination on a COVID-19 verification app, like MyIR, VaxYes, Clear, or Excelsior, or an official medical record from a provider or health department.

For those travelling internationally to D.C., a QR code or the European Union’s digital vaccine certificate will be accepted, per a spokesperson for the deputy mayor for planning and economic development.

Individuals 18 and older will need to show a form of identification in addition to their vaccination card. Forms of identification include a driver’s license or other government-issued ID card, a passport, a D.C. One Card, or a student ID card.

Will I still need to wear a mask indoors? 

Yes. The city still has an indoor mask requirement.

Can someone claim an exemption from the mandate?

People can seek either a medical or religious exemption. For a medical exemption, you must show documentation of the exemption, like a doctor’s note. For a religious exemption, someone must show “an attestation that they have a sincerely held religious belief,” according to DC Health.

Those exempt from the mandate are required to show a negative PCR or antigen test from the past 24 hours.

Who is responsible for enforcing the mandate? What if a business doesn’t comply?

Because guests are required to show their proof “upon entry,” at restaurants and bars it will likely be a host, bouncer, or another employee who normally checks ID who will ask for your vaccine card.

According to Deputy Mayor for Planning and Economic Development John Falcicchio, D.C. police are aware that enforcement begins on Saturday, and are prepared to handle any confrontations with resistant patrons.

The city’s Alcoholic Beverage Regulation Administration will issue warnings and citations to any business that doesn’t comply with the mayor’s mandate. Residents can report infractions by calling 311.

Where else in the region will I need to show my vaccine card to enter businesses?

So far, D.C. is the only major jurisdiction in our region to implement a city-wide vaccine requirement for businesses.

The Montgomery County Council introduced a measure this week that would require patrons to show proof of vaccination at restaurants, entertainment venues, and gyms, but it has yet to get a vote. If it goes into effect, starting Jan. 21, patrons 12 and older would need to show proof of at least one dose of a vaccine. Like in D.C., on Feb. 15, two doses would be required for patrons ages 12 and up. And on March 1, the mandate would extend to children ages 5 to 11.

Are there any legal challenges to the vaccine mandate?

Rep. Matt Gaetz (R-Fla.) introduced legislation on Jan. 12 to nullify D.C.’s vaccine passport, but he and his 19 cosponsors will likely have a hard time getting the bill through the Democratic-controlled Congress. He’s among a chorus of GOP leaders sounding off against D.C.’s vaccine mandates, some of whom have gone as far as to compare the mandate to Nazism.

Later this month, a national protest against vaccine mandates will take place in D.C.