A selection of quantum conferences that may be of interest:   295 meetings and counting…
Hover above the conference links to see the abstract & registration deadlines.

Indicates: ❄ winter, ☀ summer, and ❀ spring in the northern hemisphere: it's summer / (winter or spring) / autumn here of course!
❧ indicates autumn in the southern hemisphere.

On non-touch systems, hover the cursor above—on touch systems lightly touch—each data point to see the number of conferences for that month.

JUNK CONFERENCE WARNING

In modern science, as any field matures it becomes a target of predatory journals, publishers §, and meeting organisers: quantum technology is no exception unfortunately! (For those interested in the sociology of this, the New York Times has a nice recent article: A Peek Inside the Strange World of Fake Academia; also see this HuffPost article, Predatory Conferences Undermine Science And Scam Academics). Regular readers of this page have reported the following conferences as junk conferences, based on attending and/or presenting at earlier incarnations of them.
  § Another good resource is the resurrected Beall's list of predatory journals and publishers.

BIT Congress are a known predatory publisher, who "...is part of a wave of organizations that have appeared in China in past several years noted for arranging congresses with little academic merit and with the primary aim of generating revenue rather than scientific knowledge sharing." Here is the list of conferences to avoid.

EMN. Social media has lit up with colleagues complaining about spam from an organisation called EMN Meetings—mostly on private pages, but here are representative public postings by Jacob Biamonte and Heino Falke. From their website it looks like they've shut down. Result!

OMICS are a known predatory publisher, who "...started publishing its first journal in 2008. By 2015, it claimed over 700 journals, although about half of them were defunct". They run conferences that rarely—if ever!— have organisers from the field, or indeed reputable speakers. Note the URL for these conferences can be either omicsonline.org or conferenceseries.com. Either way, here is the list of conferences to avoid.
UPDATE: OMICS has been fined $50M for deceptive practices.

Oscine were a new entrant on this list, with the classic hallmarks of a predatory publisher and conference organiser. From their website,it looks like they've shut down. Whew!

Phronesis are another new entrant on this list, again with the classic hallmarks of a predatory publisher and conference organiser. Here is the list of conferences to avoid.

Scientific Federation are yet another new entrant on this list, with the classic hallmarks of a predatory publisher and conference organiser. Here is the list of conferences to avoid.

waset are a known predatory publisher, run by a former science teacher in Turkey (and his family). Readers have complained to this site about their fraudulent behaviour, for example:

I would also like to alert you that this particular organization has been using my name as their conference committee member. I am not involved at all with this organization and their conferences and have not consented for my name to be used. My university legal office has been informed and is looking into the matter. I hope you will inform your colleagues if they happen to associate me with these conferences."—Kim Guan Saw, 2 April 2015

See the comments at the end of this post for other experiences; or this warning. Comments from the former include:

In 2012 I organised an international conference ... our list of working group titles has just been copied and pasted for a WASET conference (15–16 May 2013)

The conference is a complete scam. I know I have been on several hiring committees and if we see someone list a paper published at WASET on their CV we immediately stop evaluating their application.

I went to a WASET conference and it was a complete joke. There were virtually no people there in my field, and the talks were completely unrelated to each other. Basically each person got up and spoke about their work to a completely unrelated audience. For example, the person before me talked about boat design, I talked about quantum mechanics, and the person after talked about Halal meat!

Here is the list of conferences to avoid.