Timing of email promotion. Is it important?

Well if you are seeing good results when mailing in the mid-week then stick to it.

Stick to what is working for you.

I also see you were measuring the opens, try measuring the clicks from those opens to have a more accurate test.

Yes, I did test it many times. The resulting observations are:

The best time seem to be if you catch up sending emails that will be the first thing to be seen on Monday mornings. This means 7AM in your customers' TZ, because you catch up with the early bird workaholics, and the regular crowd that comes at the normal 8-9AM just has no way to not see it ( of course if your subject is not crappy enough to land into the spam folder ). Simple as that. Midweek also performs somewhat good, having in mind that Wednesdays are somewhat relaxed - not the heavy load of stress into the first days.
And, of course, Fridays - especially afternoons - are the worst. Don't even bother sending then.

For a regular emailing ( weekly newsletter; another case not the promotional stuff in observations ) that was going out at Thu eve, because this was the publishing day, was performing bad, below average response and attention.

A lot of can depend what market you're in as I get better results mailing at weekends, unlike my marketing lists who seem to repond better to weekday mailing.

James Scholes

I have heard many different opinions about what is the best day and time to send an email but in my experience every list works differently so you just have to test and then test again...

I think Aweber tested this extensively for "open rates" in the past if I'm not mistaken.
Through their own testing they found that Sunday was the best day, followed by Saturday and Monday was the least effective.

They also found that certain times worked better for emails being opened...
8am - 50% open rate
9am - 33%

Of course these are not specifically for promotions but worth checking out.

Most studies support that sending emails on Tuesday, Wednesday or Thursday will yield the best results. While Monday's are considered the worst day to send mass emails if open rate is important to you.

This is actually an interesting subject and I think you will find every email list is completely different to the next and this is because of the demographics of each person. I have a mate who is really geeky when it comes to these kind of stats and has taken testing to a whole new level. What he did was build a completely new list by offering a really good free product, but after opting in his subscribers got sent to a small survey they had tio fill in to get the product, the survey consisted of:-
Gender
Working full time or not
location
IM experience
What Date they regularly get paid (if working)
and a few others I can't remember

Then he split the list up into different catergories and tested out a few different things! he told me that his most responsive mails were ones he sent on or around peoples paydays. With that in mind I usually mail my list around the 1st of each month as this seems to be the most common payday! but like I said, each list is different and you just have to try and take notes of all observations and make your own assessment on what works best for your list.

I find particular days of the year work really well - in the Uk we have 8-9 'bank holidays' or 'public holidays'. In the lead up to these days, I offer extreme value content, then hit them on a morning of a bank holiday with a high commission affiliate offer. Seems to work really well.

I also always experience increased ssales of my own products, too.

I also have a strategy where I look at the time people generally get paid their monthly salary. Generally, I researched that people on monthly salaries get paid on the last few days of a month, or the very first few days of the month.

I pay special attention to these days, and always offer higher priced products and affiliate products on these days, saving the lower priced deals for mid month. Works reasonably well I think, but my list is in the low hundreds.

This is a great question. I am currently testing this at the very moment. Will let you know when I have more results.

Hi Victoria,
So many great answers have already been provided but bottom line it's like James said, a lot depends on what market you're in. A friend of mine sends out 6 newsletters per week - 1 per day. She has a solid opt-in mailing list she uses and many of the same people subscribe to all 6 of the newsletters. What she told me is that each newsletter has a diff subject. One is about health, one is about celebrities, one is about hair, one about beauty and so one. She said for her target market - women between 18-45 - the celebrity newsletter gets twice as many opens as the health one.

For her the opens are not tied to specific days of the week or times, its to the subject.

Someone else with a similar newsletter marketing program might find completely different results based on times of the day, whether the people on the list are flush with cash from payday or whatever.

This is why testing works so great because it is true that every target audience is different and every gender and age group is different.

Good luck to you.