Consumer Reports has now finished retesting the battery life on Apple's new MacBook Pro laptops, and our results show that a software update released by Apple on January 9 fixed problems we'd encountered in earlier testing.

With the updated software, the three MacBook Pros in our labs all performed well, with one model running 18.75 hours on a charge. We tested each model multiple times using the new software, following the same protocol we apply to hundreds of laptops every year.

We first evaluated the MacBook Pro laptops in December, and found that battery life results were highly inconsistent from one test to the next. (They ran anywhere from a low of 3.75 hours up to 19.5 hours between charges.) That led the laptops to receive low overall scores, despite strong showings in areas such as display quality and performance.

The process we followed with Apple is the same process we follow with any manufacturer when we discover a significant problem. We shared our test results with the company so it could better understand our findings and deliver a fix to consumers. Since Apple made a fix, we retested the laptops.

Now that we've factored in the new battery-life measurements, the laptops' overall scores have risen, and all three machines now fall well within the recommended range in Consumer Reports ratings.

The three MacBook Pros in our labs include two 13-inch models, one with Apple's new Touch Bar and one without the Touch Bar; and a 15-inch model. (All 15-inch MacBook Pros come with the Touch Bar.) The new average battery-life results are, in order, 15.75 hours, 18.75 hours, and 17.25 hours. We bought the three computers at retail, as we do with other products rated by Consumer Reports, to ensure that we are testing the same models a consumer would buy.

Apple's updated software is available through Apple's Beta Software Program now, and will be rolled out in a full Software Update to all users in several weeks. According to Apple, the new software fixes a bug in Safari that caused the poor battery-life results in Consumer Reports testing.  

Consumers who want to download the new software right now have to sign up for the company's Beta program. You can confirm you have the new version by clicking on About This Mac under the Apple menu; the operating system will be listed as macOS Sierra Version 10.12.3 Beta (16D25a).