Timothy, yes it has ambidextrous manual safety. See all specs & details here >>>> ruger.com/products/rugerAmericanPistol/specSheets/8618.html ....Have a great day!

The model your asking about DOES have a manual safety.
If your looking for the version without, it's this one
budsgunshop.com/product_info.php/products_id/5158/ruger+american+pistol+45+10r />---------------
Is currently out of stock at buds hit the notify me when available button to receive an email when they come back in stock.
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There are also compact models with no safety.
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Black here
budsgunshop.com/product_info.php/products_id/27159/ruger+american+compact+45+acp+10+round />---------------------
Grey here
budsgunshop.com/product_info.php/products_id/125135/ruger++am-c+pistol+45ap+b+7rd+gray

Timothy, yes Sir, it has an ambidextrous Manual Safety Lever. Cheers and stay safe!

Yes it has a manual safety see ********Ruger American Pistol (8618)
Description:
Catalog Number: American Pistol
Model Number: 8618
UPC: 736676086184
Caliber: .45 ACP
Slide Finish: Black Nitride
Barrel Length: 4.5″
Length: 8.00″
Slide Width: 1.05″
Height: 5.70″
Weight: 32.50 oz.
Sights: Novak LoMount Carry 3-Dot
*******Safety Option: Manual Safety
Capacity: 10+1
Grip Frame: One-Piece, High Performance, Glass-Filled Nylon w/ Tac-Rail
Grips: Ergonomic Wrap-Around Grip Module
Twist: 1:16″ RH
Grooves: 6
CA Approved: No
MA Approved & Certified: No

Yes, this has an external manual thumb safety. Hope this helps. I owned the Ruger American in 45acp only difference mine didn't have the safety. But they're well made pistols, light recoil for a 45acp, good looking pistol, accurate and I'd definitely recommend one to people.