System Preferences
Choose how dates, times and phone numbers are shown throughout PrimeTask, and which day your week starts on.
System Preferences controls how PrimeTask presents information across the whole app, in task details, calendar views, the Day Planner, reports, notifications, your contacts and anywhere else a date, a time or a phone number appears.
Everything here is auto-detected from your operating system's locale the first time you open PrimeTask, so most people never need to change anything. Come here when you want to override that: European dates on a US-configured Mac, 24-hour time, a week that starts on Monday, or phone numbers formatted the way your contacts actually write them.
What you can do
Pick a date format
US, UK and European, or ISO
Pick a time format
12-hour or 24-hour
Choose the first day of your week
Sunday or Monday
Choose how phone numbers are shown
by country, or left exactly as you typed them
Leave it alone
the defaults come from your system and are usually right
How to open System Preferences
- Sidebar: Open Settings, then expand the System Preferences card.
- Settings search: Open Settings and type date, time, week, phone or format.
Things worth knowing
Your system locale sets the starting point
PrimeTask reads your operating system's regional settings on first launch and picks sensible defaults from them. A Mac set to the United Kingdom gets UK dates, 24-hour time, a Monday week start and UK phone formatting without anyone choosing anything.
Anything you set here overrides that from then on.
Try the defaults first
If you have just installed PrimeTask, open a few task dates and a contact before changing anything. The detected settings are right far more often than not, and changing them by habit is how people end up with a date format they did not want.
Date format
Three choices, each shown with a live sample so you can see the result before you commit:
- US - month first,
9/20/26 - UK and EU - day first,
20/9/26 - ISO - year first,
2026-09-20
Every date in PrimeTask follows this, including due dates, reports and notifications.
Time format
12-hour shows 11:32 AM. 24-hour shows 11:32. This applies everywhere a time is shown, including reminders and the Day Planner.
Week starts on
Sunday or Monday. This changes where the week begins in the Calendar, the Day Planner, week-based grouping and anywhere PrimeTask counts a week. See Calendar Views.
Phone numbers, and the one thing worth understanding
A phone number written with its country code is always formatted for that country, whoever is looking at it. A US number in a UK-configured app still appears as +1 (303) 555-1212, and a German number still appears as a German one. Your setting has no say over those, because the number has already said where it is from.
The setting decides one thing: what a number with no country code means. Type 020 7946 0958 with the United Kingdom chosen and PrimeTask reads it as British and shows +44 20 7946 0958. The same digits with the United States chosen are not a valid American number, so they are left exactly as you typed them.
That matters more often than it sounds, because some numbers are genuinely valid in more than one country. 303 555 1212 is a real number in both the United States and the United Kingdom, so something has to decide, and this is what decides it.
**Choose As typed to switch formatting off completely.** Numbers are then shown exactly as entered, everywhere.
Numbers PrimeTask doesn't recognise are never changed
A main line with an extension, a number with a note after it, anything unusual - if PrimeTask cannot read it as a phone number, it leaves it exactly as you wrote it. It will never rewrite something it does not understand, and it will never tell you a number is wrong.
Entering a number from another country
When you add or edit a contact or a company, each phone field has a country selector next to it. Choose the country first, then type the number, and you never need to type the country code yourself.
You can change the country afterwards and the number moves with it. This is the easiest way to add a contact abroad when all you have is their local digits. See Contacts.
Formatting is about display, not about your data
Turning formatting on does not rewrite your existing contacts. Numbers are formatted as they are shown, so every contact you already have looks right immediately and nothing is changed behind the scenes.
A number is only rewritten when you deliberately open that contact and save it. Importing contacts never rewrites them either: what the file contained is what is stored.
Phone formatting reaches further than your contacts
It applies anywhere a phone number appears, including phone custom fields on tasks and in your databases, and on PrimeFlow canvases. Set it once and everything follows.
These preferences stay on this device
System Preferences are local to the computer you set them on. They do not travel with your Spaces and they do not sync between machines. If you use PrimeTask on both a Mac and a Windows PC, set each one the way you want it.
That is deliberate: the right date format and phone country depend on where you are sitting, not on which Space you have open.
Changes take effect immediately
There is no save button. Choose an option and every date, time and phone number in the app updates as you watch.
Common questions
"PrimeTask is showing American date format but I'm in the UK."
Open Settings, expand System Preferences, and choose UK and EU for the date format. Your system locale is probably set to a US region, which is what PrimeTask read on first launch.
"I want my calendars to start on Monday."
Set Week starts on to Monday. The Calendar, the Day Planner and every week-based view follow immediately.
"How do I switch everything to 24-hour time?"
Set Time format to 24-hour. Every time in PrimeTask changes, including reminders.
"My UK mobile numbers aren't being formatted."
Check which country is chosen for Phone numbers. If it says United States, a number like 020 7946 0958 is not a valid American number, so PrimeTask leaves it alone rather than guessing. Set it to United Kingdom and it will format.
"I have contacts all over the world. Am I stuck with one country?"
No. Any number written with its country code is formatted for that country regardless of this setting, so your American, German and British contacts all look right at the same time. The setting only covers numbers that arrive with no country code, and the country selector on each phone field handles those one at a time.
"Will my formatting show up the same way for my teammate?"
Not necessarily. These preferences are per device, so a teammate sharing a Space sees dates, times and phone numbers in their own chosen formats. The underlying data is identical; only its presentation differs.
"I set this up on one Mac and my other Mac still shows the old format."
That is expected. These preferences do not sync. Set them on each computer.
"Does changing the date format change how Quick Add reads dates I type?"
Yes. Quick Add follows the same preference, so with UK and EU selected, 3/4 is read as the fourth of March. See Quick Add Settings.
Where to go next
| If you want to… | Read this |
|---|---|
| Change how the Calendar draws tasks | Time Bars |
| See how the Calendar uses your week start | Calendar Views |
| Add and manage contacts | Contacts |
| Change how PrimeTask looks | Appearance Settings |
| See every settings card | Settings Overview |