lyndacast

I have the M5, (mirrorless, crop sensor) and would like to add a lens with more reach. Is there a compatible 100-400 or 150-600 lens that I might try?
TIA

nmw1004 Loc: Dresher PA

Get an EF and EFs adapter and you can use any lens in the canon line other than the R series.

CHG_CANON Loc: the Windy City

The 55-200 and 70-300 are rather similar in image quality and 'reach'. The difference between the two will the AF speed for tracking moving subjects, with the 70-300 coming in as the better choice. The newest EF 70-300mm f/4-5.6 IS II is clearly superior to all the older EF iterations of the 70/75-300 zooms. As mentioned above, the Canon adapter makes any of the Canon branded lenses a viable option on the M5.

imagemeister Loc: mid east Florida

Staying small and light (and inexpensive), the Tamron 100-400 could be used with the EF adapter.....
.

PHRubin Loc: Nashville TN USA

Or the Tamron 150-600 G2 with the adapter

Architect1776 Loc: In my mind

Agreed, the entire EF and EF-S line=up of Canon lenses are available up to the 800mm.
Add teleconverter and you have a lot of reach.
Then add all independent EF EF-S lenses and your options are beyond comprehension.

amfoto1 Loc: San Jose, Calif. USA

You may have gathered from the previous responses... the answer is "no" and "yes"!

There is no Canon EF-M lens, as natively fit directly to the M5, longer than 200mm.

However, yes, there are a number of ways to achieve longer focal lengths.

1. Samyang/Rokinon 300mm f/6.3 "mirror" lens is very compact (as catadioptric lenses can be), BUT fully manual. Manual focus and a fixed f/6.3 aperture (neutral density filters can be used to reduce light, but will not change depth of field the way a change in aperture size would). Like other fully manual lenses, the camera doesn't "know" there's a lens installed and must be set to "shoot without lens". You can still use Aperture Priority auto exposure (Av) and Manual + Auto ISO auto exposure (M + Auto ISO) modes. You cannot use Shutter Priority (Tv) or Program (P) AE modes.... or any of the Scene modes. There is no EXIF data about the lens recorded, either. Samyang (Rokinon) 300mm lens: https://www.bhphotovideo.com/c/product/992495-REG/rokinon_300m_m_bk_reflex_300mm_f_6_3_ed.html

2. EF/EF-S to EF-M Lens Adapters are widely available from Canon and other manufacturers. https://www.bhphotovideo.com/c/products/Lens-Adapters/ci/3420/N/4077634486?filters=fct_accelerator-booster-turbo-hidden_6898%3Ano%2Cfct_camera-body-mount_1595%3Acanon-eos-m%2Cfct_lens-mount_1596%3Acanon-ef-eos

3. Those adapters allow any of the 125 million + Canon EF and EF-S lenses ever made be used on an M5. All the Canon EF 70-300mm IS USM lenses (four versions) are pretty darned good, while still being reasonably compact. The Canon EF 100-400mm lenses (two versions) are superb, though quite a bit larger and heavier. AVOID the cheap Canon EF 75-300mm "III", often sold in kit with the most entry-level models. It's Canon's worst telephoto zoom by far (slow AF, no image stabilization, poor image quality, not particularly close focusing, or very well built.... about the only thing it's got going for it is a very cheap price.... can be found used for well under $100).

Canon 70-300mm & 100-400mm zooms: https://www.bhphotovideo.com/c/compare/Canon_EF_70-300mm_f_4-5.6_IS_II_USM_Lens_vs_Canon_EF_70-300mm_f_4-5.6_IS_USM_Lens_vs_Canon_EF_70-300mm_f_4-5.6L_IS_USM_Lens_vs_Canon_EF_100-400mm_f_4.5-5.6L_IS_II_USM_Lens/BHitems/1281379-REG_397663-USA_732106-USA_1092632-REG

Canon EF 300mm f/4L IS USM is lighter and smaller than the 100-400s, but by the time you add a 1.4X teleconverter to it, ends up weighing and sized about the same. The [b]Canon EF 400mm f/5.6L USM[/u] also is excellent, too, but doesn't have image stabilization. Canon 300mm, 400mm and 1.4X: https://www.bhphotovideo.com/c/compare/Canon_EF_300mm_f_4L_IS_USM_Lens_vs_Canon_Extender_EF_1.4X_III_vs_Canon_EF_400mm_f_5.6L_USM_Lens/BHitems/129188-USA_732113-USA_12129-USA

4. There are also many third party lenses in Canon EF/EF-S mount that can be used with the same lens adapters. I'm not aware of any specific compatibility issues adapting for use on the M5, but those have happened sometimes in the past between certain 3rd party lenses and newer cameras. Just be sure to carefully research any specific 3rd party lens you might be considering.

Lenses to consider would be the Tamron and Sigma 100-400mm, which are pretty good and considerably lower cost than, though not in the same class as the Canon 100-400s. Between the Sigma and Tamron 100-400s, I'd be inclined to consider the Tamron since it can optionally be fitted with a tripod mounting ring. There's no provision for that on the Sigma lens. (The Canon 100-400s incl. a tripod ring.) The Tamron and especially the Sigma are also "slower" than the Canon lenses. The 3rd party lenses' max apertures are smaller. The current Canon 100-400 II is up to 2/3 stop faster than the Sigma, through much of the zoom range.

There also are the Sigma and Tamron 150-600mm lenses (and no comparable Canon... yet). There have been two of each. Tamron's "G2" is their latest and improved quite a bit over the first version. Sigma offers two different... a more affordable "contemporary" or "consumer grade" version and a bigger, heavier, more robust "sports" or "pro grade" version. The last is the best of the bunch, but comes with a hefty price tag and is a lot more lens to haul around.

There is also now a Sigma 60-600mm lens. I don't know much about it, other than what the specs tell me (it's rather large and heavy).

Tamron & Sigma 150-600mm, 60-600mm (adapter req'd): https://www.bhphotovideo.com/c/compare/Sigma_150-600mm_f_5-6.3_DG_OS_HSM_Sports_Lens_for_Canon_EF_vs_Tamron_SP_150-600mm_f_5-6.3_Di_VC_USD_G2_for_Canon_EF_vs_Sigma_60-600mm_f_4.5-6.3_DG_OS_HSM_Sports_Lens_for_Canon_EF_vs_Sigma_150-600mm_f_5-6.3_DG_OS_HSM_Contemporary_Lens_for_Canon_EF/BHitems/1082152-REG_1277358-REG_1436262-REG_1082154-REG

Some older 3rd party lenses may be worth considering. Sigma offered 120-400mm, 150-500mm and 50-500mm. If you consider these, I'd encourage you to look for the "OS" versions, with built in image stabilization. Not only is that a helpful feature, but the OS versions are also the most recent models of these lenses, with other improvements as well. All these lenses were discontinued some years ago, will now only be available used, and may be difficult to get serviced or repaired, if it's ever needed.

There also are Tamron 70-300mm lenses that may be worth a look. I really don't know much about them, but I notice the more expensive one has image stabilization and faster ultrasonic focus drive: https://www.bhphotovideo.com/c/compare/Tamron_Zoom_Telephoto_AF_70-300mm_f_4-5.6_Di_LD_Macro_Autofocus_Lens_for_Canon_EOS_vs_Tamron_SP_70-300mm_f_4-5.6_Di_VC_USD_Telephoto_Zoom_Lens_for_Canon_Digital_SLRs_%26_35mm_Film_Cameras/BHitems/423725-REG_728341-REG

You'll notice that many of the above lenses have a tripod mounting ring or at least the option to install one (though NOT the Samyang/Rokinon 300mm, Sigma 100-400 and any of the 70-300s except for the Canon "L"). Longer focal lengths such as these will be more challenging to hold steady for a sharp shot.... particularly when used on a small, lightweight camera like the M5. It will very likely be useful to have option to mount on a tripod or at least a monopod. Most of the lens adapters also have a tripod mounting foot, although those do not allow rotation of the camera and lens, the way a true tripod mounting ring does.

kcooke Loc: Alabama

I purchased an M5 to use as a travel camera in January. Also to see if I like mirrorless. B&H had them at half price.
Including the little 15-45 mm M series lens. I now have the Canon brand converter and it works very well. I have used it with 17-40 L , 24-105L and
100-400L. It works fine; its just an adjustment on how you shoot and support the lens with you hand. The camera is tiny on the 24-105 and on the 100-400 it’s micro sized. It looks kind of funny.

Architect1776 Loc: In my mind

That is why the R series are not so microscopic. Looks plays a part, like other things if they look right then likely they are.
The M series is designed as you say to be small, small lenses for easy portability.