Update on Dexcom G5 3-Month Transmitter Battery Life

This isn’t very exciting news for those of us fortunate enough to have our CGM covered by insurance. However, its pretty significant news for those who have to self-fund.

I had originally been told by Dexcom that the G5 transmitter would automatically shut off at 3months. The rep explained that at the 3-month period, I would get a notification stating I was on my last sensor (it wouldn’t just shut off without any notice) and then it would automatically stop.


12/24 was the 3-month date from the start of my first G5 transmitter. I didn’t receive a notification. However, it read “Your transmitter battery is low. The transmitter will stop working in about three weeks. Check your email inbox for more details.”

So far nothing in my inbox, but either way it’s good knowing the G5 system works similar to the G4 in allowing you to operate it past the recommended time window.

I am still debating if I want to test the battery’s lifespan. Currently, I plan to but that may change depending on my schedule in the upcoming months. I’m very fortunate that the system is covered by my insurance, but you never know when that could change.

Bottom line: the Dexcom G5 system can be run longer than the 3month recommended lifespan if needed.


Great new. Thanks for the update! My 3 month window should be ending any day now, was wondering if I should get the 2nd transmitter ready.

Thanks, that’s good to know. I hope you can push it till it’s dead. It’d be nice to know how far past the 3 months it can go. I realize that there’s probably a spectrum of performance but this is the kind of thing that several of us can do to crowd-source some data. It would be useful to know, for instance, that the typical G5 transmitter can actually last 4 months give or take a few weeks, for example.

I look forward to seeing more posts on this. I’m still waiting for my current G4 transmitter to signal its end before I put in place my first G5 transmitter.

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To be clear: Dexcom has said it will last 108-112 days. That is the three-month transmitter life, plus a gap period to allow for you to obtain a new sensor.

And one other point: 3 months plus 3 weeks of transmitter life is NOT the same as G4, which many report will last months beyond the six-month period it’s designed for.

Still hoping it lasts longer than that, though, despite what the engineers designed it to do and shutoff.


A few comments:
1.) Please link us to where Dexcom mentioned the 108-112 day lifespan. I’m not disagreeing with you, but that’s not what was conveyed to me. I’ve spoken with Dexcom’s customer support on three separate occasions about the issue, and those estimations were never provided to me. The only direct answer I received was what I mentioned previously: The transmitter would provide an alert at the 90-day mark notifying the user that they were on their last sensor. I was told it would automatically shut off after that point. Again, my original post was confirming that information was untrue.

2.) I am well aware that the G5 transmitter life is not identical to the G4. However, that was never the intention of my point. G5 transmitters are shipped in packs of two (in the US) to combat the 3-month estimated battery life of the G5 versus the 6-month estimated battery life of the G4 transmitter.
The issue raised by many people outside of the US was about whether or not the G5 could be used beyond its estimated battery life or if it would automatically shut off. My original post attempted to explain that the G5 acts in the same manner as the G4 by not having an automatic shut-off feature. It was never my intention to suggest the two systems had identical battery lives.

Is your transmitter 90 days or 108/112 days old? If it hasn’t been 90 days plus the grace period then you still don’t know for sure that there is not an auto shut off. I was told by Dexcom customer support that I would get an alert at 90 days but that the Gen 5 transmitter would stop transmitting on day 108.

I, too, would like to know if the G5 transmitter is hard-wired to a fixed number of service days. I’ve read conflicting info on this. We should know soon as the first wave of G5 adopters are coming up on their 90-day service anniversary. Do you plan on running the G5 until it runs out of juice?

That whole fixed service time shut-off is off-putting to me. I’m hoping it’s not true. I’d like to think that the uncertain balance of juice over the published 90-day warranty will accrue to the user.

It seems there is some confusion. At this point, I am confirming one thing: the transmitter doesn’t automatically shut off at 90days/3-months.

Timeline of events:
9/24/15- My transmitter is activated
On 12/24/15- I received a notification within the Dexcom app that read “Your transmitter battery is low. The transmitter will stop working in about three weeks. Check your email inbox for more details.”
12/28/15 (Today)- My transmitter is still working and I have not received any further notifications (or anything in my email inbox).

It seems some of you have been given significantly different information from what I received from Dexcom’s customer support. I’m not confirming or denying any of that information aside from what I wrote above. I have zero affiliation with Dexcom and I’m only sharing my personal experiences with the G5 transmitter and my calls to Dexcom’s customer support.

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I just hit my 3-month mark on the G5 transmitter and this is what I got…

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So this appears to be a hard-wired battery expiration of 3 months + 3 weeks like @Michael_Hoskins wrote. Maybe Dexcom is doing this since a fading battery produces an inaccuracy that might clinically mislead. Well, a 3 week bonus is not as good as the 4-8 month bonus common with the G4 but it is 6 weeks better than the warranty period for 6 months (2 transmitters). I suppose others can confirm your experience. Thanks for the screen shot.

Dexcom’s VP of strategy and commercial development, Steve Pacelli, confirmed the 3 months + grace period information. This was directly asked of him, and he confirmed it’s true. This is what I wrote at DiabetesMine. In a podcast interview in late September/early October, he talked around that point but did not specifically say YES or No – that created quite a bit of confusion within our D-Community. I triple-checked multiple times with customer service, two different Dex sales reps, and even the guy who created the hardware behind G5, and they all said that it was designed to shut off – unlike the G4, which runs until it dies.

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The related thread regarding replacing the batteries in a G4 might also have something to do with the company’s strategy to give the G5 a hard expiration date.

I just got my warning yesterday about it having about 3 weeks of battery left. My transmitter activation date was 9/28. I’d be curious to know the reasoning behind a hard shutoff. I’m leaning towards @Terry4 's thoughts of the concern of inaccuracy if the battery is getting low.

also, as a follow up, I’m curious to see if we can “re-start” the transmitter like we do a sensor? The sensor has a hard shut off of 7 days and most of us just restart it. Will be curious to see if this works with the transmitter or if anyone here has tried it.

We’ve all come to enjoy the bonus economy of the “seven-day sensors.” I am suspicious of most corporations’ tendencies to make economic decisions that favor the company at the expense of consumers. Dexcom has always been like a breath of fresh air in that they’ve under-promised and over-delivered. I hope this instance does not mark a change of practice. I wish their communication was clearer about this decision to hard-wire the G5 transmitter life span.

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It would be really nice of the G5 transmitter doesn’t shut off, but I don’t think three weeks “extra” is all that significant for anyone who is paying for this technology themselves. If each G5 transmitter lasts three months and three weeks, two G5 transmitters (which cost the same as one G4 transmitter) would still be hardwired to die after seven and a half months. I’m using a G4 and pay $800 per transmitter, and my current (first) transmitter is approaching its tenth month of use. I will use it until the day it dies before paying $800 for another one, and to me two and a half months (or hopefully longer) is a significant amount of residual battery power to just discard.

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Awesome information. I’d encourage you to share it around the other various diabetes forums.

There are a lot of people (especially in the UK) who are holding out on buying the G5 due to the uncertainty of how long it will last. Apparently, the distributor in the UK only ships them individually (rather than 2 at a time).

Thanks for sharing.

Did you also receive the warning screen included in Anthony’s post (quoted below)? The bit about the email is unexpected so I’ve always been wondering what may be up with that. :confused: Oh, well.

FWIW, 22 days from 24 Dec 2015 should be January 15, 2016, give or take a day depending on how you want to count the days. So I guess we’ll have to check back in around that time to see what happens.

I did receive the message Anthony posted a screen shot of (albeit a bit late since I never use the Dexcom receiver).

A small update, but I activated a new sensor two days ago (1/3/16) and did receive the message Dexcom’s customer support had mentioned to me. I didn’t get the screenshot but it said something to the tune of “Transmitter battery low. this will be your last sensor before needing to replace your current transmitter.”

Cut-off time will be 1/10/16 and after that I should be able to report exactly what happens without any speculation.

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Ok, My G5 just arrived and my G4 is still working. So you are saying that the sensors in the G5 only last 3 months compared to the G4 which lasts for a year? I’m just wondering why my sales rep did not tell me this information and also, why did Dexcom change that? Besides money. So we have to now buy a new sensor 4 times a year? My concern is that I’m being laid off at the end of Februrary and will only have insurance for 6 months after that. I can’t imagine any insurance company will take me as I’ve had diabetes for 51 years! Tell me it isn’t so! So it would be best to start the new one right away - it’s still in the box - as my G4 works fine and I was hoping it would last and wait for me.
Any info is appreciated!!