The iPhone XR and XS are not waterproof. But they are water resistant, and you can take them for a swim without too much concern -- even in salt water.

According to Apple, the iPhone XR can survive a dunk up to 1 meter (3 feet) for 30 minutes, meeting the IP67 standard. The more expensive iPhone XS and XS Max can withstand double that: 2 meters for 30 minutes, aka IP68.

Video: How deep can the iPhone XS and XR go?

But outside the official ratings, how deep can these phones really go?

We've already put the XS to the test in our earlier water test, and it survived being submerged in chlorinated pool water for 30 minutes. It wasn't fazed by splashes of hot tea, wine or a shallow swim in the salt water of the San Francisco Bay either.

To raise the stakes, we took a new iPhone XR and the same XS that survived our initial pool test to Monterey Bay in California. We strapped the two phones to the front of the Trident, an underwater drone from OpenROV. It can reach depths of up to 100 meters, although the bay isn't anywhere near that deep.

Lexy Savvides/CNET

To help get our phones under the water without them drifting away, OpenROV built a custom mount just for us with flotations to hold the phones side-by-side in front of the lens. Before submerging the phones, we set the screens to stay on and set a timer.

Watch the video on this page for the full rundown of what happened -- and check out the epic underwater footage!

This isn't a scientific test, and be advised any sort of water or liquid contact may cause damage to your phone. Apple specifies that water damage is not covered under warranty.

The first dive: 2 meters

Seeing as we haven't previously tested the iPhone XR's water resistance, we decided to put both phones on the drone and dive down to 2 meters. The iPhone XS is designed to hold up to this just fine, but the iPhone XR isn't supposed to go that deep.

After about 5 minutes of being submerged in the bay, we pulled the drone out of the water. Drying off both phones with a microfiber cloth, the touchscreens on the iPhone XR and iPhone XS were still fully functional. There was no evidence of water ingress or fogging on the lens. Buttons and speakers still worked.

That being said, because the iPhone XS had already been dunked previously, its speakers sounded more muffled and less clear than those on the iPhone XR, which sounded perfectly fine.

Lexy Savvides/CNET

The second dive: 3 meters

For round 2, we put the phones back on the drone, started the timers again, and let them go down to 3 meters. Once they had bobbed around in the currents for another 5 minutes, we brought them up again, cleaned them off and inspected them.

Again, both phones were fully functional. There was no evidence of any water damage to the phones, but the iPhone XS speaker still sounded muted compared to the iPhone XR.

Andy Altman/CNET

The third dive: 5 meters

For the next attempt, we upped the ante to see just how much these phones could take. The depth was 5 meters and we left them for around 19 minutes before pulling them out of the bay.

OpenROV

Apart from capturing some amazing underwater wildlife swimming in the background, nothing out of the ordinary happened. The phones were still fine once we dried them off and tested them.

The final dive: 8 meters

Both phones survived far greater depths than they were rated for, even though we didn't leave them in for 30 minutes at a time. So we took them to the bottom of Monterey Bay, around 8 meters. This time, we decided to leave them for as long as we could (that is, until the recording space on the drone ran out).

For the first few minutes, both phones were performing fine underwater. But around 3 minutes in, the iPhone XR flashed a warning on screen about the SIM card. It was the first sign that anything was wrong with the phone and indicated that water had made its way into the SIM tray.

The iPhone XR held on for a little longer, but after 6 minutes, 50 seconds, the screen went completely black. The iPhone XS, on the other hand, was still going strong. We left it submerged until we hit the 30-minute mark.

Andy Altman/CNET

After pulling both phones up to the surface, the iPhone XR was completely down for the count. We dried it off and tried to turn it on, but nothing. Removing the SIM card tray resulted in a big splash of water coming out of the cavity.

That wasn't all. The iPhone XR also looked like it had developed a slight bulge in the screen, as it separated slightly from the side of the phone (this was the same side as the SIM tray).

Bear in mind again that the phone was submerged to around eight times the depth it was rated for, and it had been dunked for sustained periods previously as we went down into the bay. The fact that it survived up until this depth was a genuine surprise.

But the biggest surprise was that the iPhone XS had zero signs of water damage, apart from the same muffled speakers we'd previously noted. We checked inside the SIM tray to see if the Liquid Contact Indicator had been activated, but nothing was visible.

A week after this water test, the iPhone XS was still going strong. The speakers were mostly recovered, but there was still a little distortion when playing back heavy bass or lower frequencies. Turns out if your iPhone XS goes for a deeper swim than expected in salt water, it might just survive.

Originally published Nov. 17. Updated Nov. 20.

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