Miro responded on social media with her own sweet message.
\"Time flies when you're having fun. Happy anniversary baby I love you too @zacefron September 5,\" she wrote.
The pair met last year through mutual friends while Efron was shooting his latest film \"We Are Your Friends,\" which flopped at the box office.
The former marketing executive, who ditched her corporate job to pursue a career in vintage fashion, opened up about their relationship to Elle.com in March.
\"I've never spoken about us before, but, um, it's definitely different,\" Miro said about dating a Hollywood celebrity. \"I think that you have to take that [kind of attention] with a grain of salt, and put yourself in other people's positions. I think that's actually a really big part of it, putting yourself in their shoes, and trying to understand where they're coming from, and then it kinds of makes sense. It kind of just comes with the territory, and I know there's no really changing that, so you have to just embrace it.\"
","publishedDate":"2015-09-08T15:13:43Z","contributors":[{"name":"ABC News","url":"","role":"","logo":"","logoAlt":""}],"modifiedDate":"2015-09-08T15:13:43Z","section":"Entertainment","wordCount":242,"relatedTags":{"heading":"Related Topics","tags":[]},"lead":{"ratio":"16x9","disableForMobile":false,"type":"xl","mediaType":"image","alignCaptionToBody":true},"ads":{"Sticky":{"kvps":{"test":true}},"RightRail":{"kvps":{"test":true}},"InlineBox":{},"InlineOutstream":{"disabled":false},"Taboola":{"position":"bottom","pageType":"article","config":{"network":"abcnews-abcnews","mode":"thumbnails-a","container":"taboola-below-article-thumbnails","type":"article","targetType":"mix","placement":"Below Article Thumbnails"}}},"featuredVideo":null,"featuredImage":{"caption":{"credit":"@samimiro/Instagram ","text":"Sam Miro posted this photo to Instagram on Sept. 8, 2015 with the caption, \"Time flies when you're having fun. Happy anniversary baby I love you too @zacefron September 5.\"","lines":2},"image":{"alt":"Sam Miro posted this photo to Instagram on Sept. 8, 2015 with the caption, \"Time flies when you're having fun. Happy anniversary baby I love you too @zacefron September 5.\"","src":"https://s.abcnews.com/images/Entertainment/ht_efron_kab_150908_16x9_992.jpg?w=1600","sources":[{"min":0,"max":374,"src":{"x1":"https://s.abcnews.com/images/Entertainment/ht_efron_kab_150908_16x9_992.jpg?w=384"}},{"min":375,"max":693,"src":{"x1":"https://s.abcnews.com/images/Entertainment/ht_efron_kab_150908_16x9_992.jpg?w=608"}},{"min":694,"src":{"x1":"https://s.abcnews.com/images/Entertainment/ht_efron_kab_150908_16x9_992.jpg?w=1600"}}],"fetchPriority":"high"}},"dateline":"—","seo":{},"LivePromotion":{}},"autoUpdate":{"enabled":false,"topics":["general-elections-2020-balance-of-power"]}},"upw":{"balanceOfPower":{"electoral":{"header":"Biden Projected to be President-Elect","candidates":{"democrats":{"id":1036,"displayName":"Joe Biden","shortDisplayName":"J. Biden","firstName":"Joe","lastName":"Biden","party":"democrats","major":true,"incumbent":false,"winner":true,"votes":306},"republicans":{"id":8639,"displayName":"Donald Trump","shortDisplayName":"D. Trump","firstName":"Donald","lastName":"Trump","party":"republicans","major":true,"incumbent":true,"winner":false,"votes":232},"other":{"displayName":"Other","votes":0}},"parties":{"democrats":"democrats","republicans":"republicans"},"type":"electoral","votes":{"democrats":{"available":{},"total":306,"difference":{},"popular":{"displayValue":"81,283,098","value":81283098}},"republicans":{"available":{},"total":232,"difference":{},"popular":{"displayValue":"74,222,958","value":74222958}},"other":{"available":{},"total":0,"popular":{}},"total":538},"needed":{"displayText":"270 to win","displayValue":"270","value":270},"lastUpdated":{"value":"2020-12-18T21:15:13.850Z","displayValue":"December 18, 4:15:13PM ET"},"reporting":"99% of Expected Vote Reporting"},"senate":{"header":"Senate Seat Results","candidates":{"democrats":{"displayName":"Democrats","icon":"party-democrats","votes":46,"winner":false},"republicans":{"displayName":"Republicans","icon":"party-republicans","votes":50,"winner":false},"other":{"displayName":"Other","votes":2}},"parties":{"democrats":"democrats","republicans":"republicans"},"type":"senate","votes":{"democrats":{"available":{"displayText":"12 Democrats up for election","shortDisplayText":"12 Dems. up for election","displayValue":"12","value":12},"total":46,"difference":{"displayText":"Gained 1 seat","displayValue":"1","value":1},"popular":{}},"republicans":{"available":{"displayText":"23 Republicans up for election","shortDisplayText":"23 Reps. up for election","displayValue":"23","value":23},"total":50,"difference":{"displayText":"Lost 1 seat","displayValue":"-1","value":-1},"popular":{}},"other":{"available":{"displayText":"0 Others up for election","shortDisplayText":"0 Others up for election","displayValue":"0","value":0},"total":2,"popular":{}},"total":100},"needed":{"displayText":"51 for control","displayValue":"51","value":51},"lastUpdated":{"value":"2020-12-17T18:22:05.390Z","displayValue":"December 17, 1:22:05PM ET"}},"house":{"header":"House Results: Dems Retain Control","candidates":{"democrats":{"displayName":"Democrats","icon":"party-democrats","votes":222,"winner":true},"republicans":{"displayName":"Republicans","icon":"party-republicans","votes":210,"winner":false},"other":{"displayName":"Other","votes":0}},"parties":{"democrats":"democrats","republicans":"republicans"},"type":"house","votes":{"democrats":{"available":{"displayText":"233 Democrats up for election","shortDisplayText":"233 Dems. up for election","displayValue":"233","value":233},"total":222,"difference":{"displayText":"Lost 10 seats","displayValue":"-10","value":-10},"popular":{}},"republicans":{"available":{"displayText":"201 Republicans up for election","shortDisplayText":"201 Reps. up for election","displayValue":"201","value":201},"total":210,"difference":{"displayText":"Gained 10 seats","displayValue":"10","value":10},"popular":{}},"other":{"available":{"displayText":"1 Others up for election","shortDisplayText":"1 Others up for election","displayValue":"1","value":1},"total":0,"popular":{}},"total":435},"needed":{"displayText":"218 for control","displayValue":"218","value":218},"lastUpdated":{"value":"2020-12-17T18:22:02.900Z","displayValue":"December 17, 1:22:02PM ET"}},"lastUpdated":{"value":"2020-12-18T21:15:13.850Z","displayValue":"December 18, 4:15:13PM ET"},"autoUpdate":{"enabled":false,"topics":["general-elections-2020-balance-of-power"]},"electionsConfig":{}},"types":["electoral","senate","house"]}},"analytics":{"accountID":"wdgnewabcnews,wdgasec,wdgnewabcnweb,wdgnewabcnewsrollup","ns":"abcnews","pageName":"abcn:entertainment:story","pageType":"story","pageUrl":"abcnews.go.com/Entertainment/zac-efron-celebrates-year-anniversary-girlfriend-sam-miro/story?id=33602438&userab=abcn_web_article_ts-218*variant_b-819","globalSpecVersion":"v1.08","siteDifferentiator":"abcn:site","tagID":"apage_news01","userABCookie":"abcn_web_article_ts-218*variant_b-819","alertTag":"none","authors":"ABC News","authorsBureau":"none","authorsUnit":"none","dateline":"—","id":"33602438","modDate":"2015-09-08","mediaOnPage":"image","modTime":"11:13","provider":"ABC News","pubDate":"2015-09-08","pubTime":"11:13","section":"Entertainment","subBrand":"none","title":"Zac Efron Celebrates One-Year Anniversary With Girlfriend Sam Miro","videoId":"none","videoName":"none","wordCount":242},"taboola":{"config":{"network":"abcnews-abcnews","mode":"thumbnails-a","type":"other","targetType":"mix","placement":null,"pageTypeOverrides":{"story":{"mode":"thumbnails-a","type":"article","targetType":"mix","placement":"Below Article Thumbnails"},"home":{"mode":"thumbnails-b","container":"taboola-homepage-thumbnails","type":"home","targetType":"mix","placement":"Homepage Thumbnails"},"section":{"mode":"thumbnails-b","type":"category","targetType":"mix","placement":"Section Front Thumbnails"},"liveBlog":{"mode":"thumbnails-d","type":"other","targetType":"mix","placement":"Blog"}}}}},"request":{"headers":{},"httpVersion":"1.1","method":"GET","url":"/Entertainment/zac-efron-celebrates-year-anniversary-girlfriend-sam-miro/story?id=33602438&userab=abcn_web_article_ts-218*variant_b-819","vary":{"host":"abcnews.go.com","cached":true,"path":"/Entertainment/zac-efron-celebrates-year-anniversary-girlfriend-sam-miro/story","forwarded-proto":"https","device":"desktop","country":"us","userab":"abcn_web_article_ts-218*variant_b-819","region":"gdpr"}},"viewport":{"width":1260,"height":0},"user":{}};
