When to Send Follow-Up Emails: Picking Your Days, Hours, and Time Zone

A painter I know set up a follow-up to chase everyone who had a quote sitting unanswered. Twenty-two homeowners. He wrote it on a Sunday evening, hit send, and went to bed pleased with himself.

The emails went out at 11pm Sunday. Two people unsubscribed. One replied asking to be taken off "whatever list this is." Nobody booked.

The message was fine. He had picked good customers and written a warm, specific note. The problem was the clock.

Why the hour changes the outcome

An email that arrives at 11pm on a Sunday reads as automated, because almost nothing a real person sends arrives at 11pm on a Sunday. Your customer does not consciously think "this is a bulk send." They just feel that it is, and the feeling shows up as a delete or an unsubscribe instead of a reply.

Mail providers watch the same signal. Gmail and Outlook both weigh when your mail goes out, how fast, and how people react to it. A burst of near-identical messages leaving one address in the middle of the night is one of the clearest automation fingerprints there is, and the penalty does not stop at your campaign. It follows the estimate you send by hand on Monday morning from the same address.

So the hour is not a nicety. It is part of whether your business email works at all.

What good timing actually looks like

The safe default for most small businesses is weekday mornings, inside normal working hours. Nine to half four, Monday to Friday, is the shape RadiusOS ships with, and most people should never change it.

Most, not all. The default assumes an office week, and plenty of businesses do not run one:

• Landscapers and painters often do their best booking on a Saturday morning, when the homeowner is standing in the garden looking at the thing that needs doing.
• Real estate agents live on weekends. A Sunday afternoon follow-up after an open house is the most natural message in the world, and cutting weekends off would mean sending it two days late.
• Anyone selling to other businesses should stay well inside the working week, and often wants to skip Monday morning, when an inbox is at its most hostile.
• A shop that closes Fridays should not be mailing customers on a day nobody is there to answer the reply it produces.

"Business hours" means something different in every trade. Yours is the one that counts.

Setting your days and hours

In RadiusOS this lives in one place: Settings, then Sending limits, under "When to send."

There is a row of seven circles, one per day. Tap a day to switch it on or off. Below that, Start and Stop set the hours, and a time zone dropdown says whose clock those hours belong to.

Underneath all of it is a sentence that reads back what you chose:

Follow-ups go out Mon to Fri, 9:00 AM to 4:30 PM PDT.

That sentence is the thing to actually read. Five separate controls are hard to check against each other, and a sentence is not. If it says what you meant, you are done.

The same line appears on your Group emails page and on every campaign, so you never have to remember which schedule a send is following.

The time zone trap

Here is the one that catches almost everybody, and it is worth two minutes of your attention.

Your sending schedule runs on a time zone you choose. Left alone, that zone might not be the one you are sitting in. A contractor who set up on Eastern time and then moved to Arizona, or who is simply checking their phone in a different state, gets a strange experience: the schedule says nine in the morning, and the campaign screen appears to say six.

Both numbers were right. They were just different clocks, and nothing on the screen said so.

RadiusOS now prints the zone on every send time in the product:

Goes out Mon, Sep 1 at 9:00 AM PDT

Times on the campaigns list, on each campaign, on every recipient row, and in the composer all use your sending zone and all name it. If a time looks wrong, you can now see immediately whether the schedule is wrong or you are reading it in the wrong clock. Usually it is the second one.

Changing your mind halfway through a send

A group email does not go out all at once. It goes out over hours or days, at a pace that keeps your address in good standing, which means there is a real chance you will want to change the schedule while one is still running.

You can. Change the days, the hours, or the zone, and save. Everything still waiting in the queue moves onto the new schedule, and the confirmation tells you how many messages moved:

Saved. 5 queued messages were moved to the new schedule.

Open the campaign afterwards and every waiting message shows its new time. What has already been sent stays sent. Nobody can pull an email back out of somebody's inbox, and a tool that implied otherwise would be lying to you.

A worked example

Back to the painter. Here is the setup that would have saved him:

• Days: Monday through Saturday. Saturday morning is when homeowners look at their houses.
• Hours: 8:00 AM to 5:00 PM. He starts early and so do his customers.
• Time zone: the one he actually lives in.

Written on a Sunday evening, the same campaign now waits. The first message goes out at 8:00 the next morning, the rest trickle out across the week inside those hours, and the summary line on the campaign says exactly that before he ever clicks send.

Same list. Same words. A reply rate that is not sabotaged by the clock.

The short version

• Weekday working hours is the right default. Change it when your business genuinely runs on a different week.
• Check your time zone once. It explains almost every send time that looks wrong.
• Read the summary sentence. It is faster and more reliable than checking five controls.
• You can change the schedule mid-campaign, and anything still queued will follow it.

Set it once, and every follow-up you send from then on arrives at an hour a person would actually have sent it.

How sending limits work covers the volume side: daily and hourly caps, the gap between messages, and the warm-up on a new sending address.