Woah, crazy there isn't a way to do this. It's so embarrassing to accidentally save a pdf with default settings and have hidden objects appear when the client tries to print. If you're needing to save several projects a day, it's so easy to forget to change the option once. I NEVER want to use Illustrator Default, and the way it makes invisible layers appear for printing is ridiculous. How is this not an option yet? This thread was posted five years ago.

Too many resources spent on their marketing and customer-money-squeezing department and not enough on making their product professional-customer friendly?

While we wait for this change, we can use a script to save the file in the desired PDF preset.

Just save a JSX file with this code:

function saveAsPDF() {
var pdfFile = new File(app.activeDocument.path + "/" + app.activeDocument.name.split('.')[0] + '.pdf');
var pdfOptions = new PDFSaveOptions();
pdfOptions.pDFPreset = "[PDF/X-1a:2001]"; //insert the preset name as it's written in Illustrator
app.activeDocument.saveAs(pdfFile, pdfOptions);
}
saveAsPDF()

Then run the script by adding it to your Illustrator scripts folder or other methods like AutoHotKey, drag and drop... I use Streamdeck to run it.

To not have the warning every time you try to run the script, create this single time use script:

#target illustrator

app.preferences.setBooleanPreference("ShowExternalJSXWarning", false);

yes please

Totally agree - come on adobe, listen to your customers - save to .pdf (set smallest size to default) would save me hours a week.

This has been annoying me too. Seems like it would be such an easy thing to do and it would help users so much!

In "Save Adobe PDF" option dialog box, when saving as pdf, please, remember my last Preset selection as I have to keep reselection "Press Quality", for example, every time, because it always shows the default "Illustrator Default" preset.
it would be a time saving not clicking two more times in the saving process.

Absolutely! How easy it is forget to output settings to include profiles when you are in a hurry!
MisprintsRus

Great idea!!! I wish they'd fix the little things like this, rather than the yearly updates that add nothing but the need to update my MacOS on an old machine that can't handle another update.

The adobe developer team produce more bugs.
But the program surface now: blink blink.
Good work!

I'm saving 50+ PDF's per day and none are Illustrator default. This would make life super easy.

Someone on the dev team is really dug in on this one. I had a really busy day yesterday and saved almost 70 pdfs (not including save overs). And now I'm dealing with the program bug that if you do a save-as and change the file name, the next pdf is still the old file name... plus the copy copy copy copy etc if you resave a lot in the same file. Makes me miss Illustrator 1.1 thu 9 when the program did everything it was supposed to do in a sensible manner. I'll have 34 years of ai use this October... man this one twists me up.

An update today, and still this feature is missing. It has been available in InDesign for years! Adobe, are you listening to your users?

@ Alex, I have noticed the same thing in the last two Illustrator updates. I have actions setup to save PDF's for a particular workflow and they *used* to save with their selected joboptions correctly, but now they're doing what export for screens does (a bug) that just uses the most recently used 'save as' PDF settings, regardless of anything else.

I have to be careful to manually save a pdf with the settings I want and then run my actions.

how is this still not a thing? Make it happen Adobe!

I have a similar issue here. I deal with several PDF, some are in RGB other in CMYK. I created several actions inside Illustrator so I don´t have to repeat the same step requested in the Save As… menu. But today I found that these presets are not fixed to each action. I found these actions use the last PDF modification made. If I have created a particular CMYK PDF by hand and then I try to use my RGB action, it won't work, because it will create a CMYK file even though I have created an RGB preset.

The crazy thing is that InDesign has had this capability for years! It shouldn't be that difficult to implement in Illustrator, as well. PLEASE, ADOBE, PLEASE MAKE THIS HAPPEN!!!

Just jumping in to agree. Can't even believe there isn't a way to modify your defaults based on your own preferences.

Here's another vote for being able to set my own default for exporting PDFs. We all jump through this silly hoop over and over again, day after day.

Guess I should better attention. I've downloaded the last two pre-release builds and then not installed them. And after the last terrible terrible update to Photoshop I've decided to slow my boat on blind updating. Thanks though Cameron, I'll will use this .ai update.

@Rick Wallace Background filesaving just got released!

https://helpx.adobe.com/illustrator/using/saving-artwork.html#background_save