Wiggs began writing as a child, finishing her first novel, A Book About Some Bad Kids, when she was eight. She temporarily abandoned her dream of being a novelist after graduating from Harvard University, instead becoming a math teacher. She continued to read, especially reveling in romance novels. After running out of reading material one evening in 1983, she began writing again, using the working title A Book About Some Bad Adults.

For three years Wiggs continued to write, and in 1987 Zebra Books published her first novel, a Western historical romance named Texas Wildflower. Her subsequent historical and contemporary romances have been set in a wide range of settings and time periods. Many of her novels are set in areas where she's lived or visited. She gave up teaching in 1992 to write full-time, and has since completed an average of two books per year.

In 2000, Wiggs began writing single-title women's fiction stories in addition to historical romance novels. The first, The You I Never Knew, was published in 2001. After writing mass-market original novels for several years, Wiggs made her hardcover debut in 2003 with Home Before Dark.

Many of her novels are connected, allowing Wiggs to revisit established characters.

Her books have been published in many languages, including French, German, Latvian, Japanese and Russian.

Wiggs's books are frequently named finalists for the RITA Award, the highest honor given in the genre. She received the Romance Writers of America RITA Award for Best Romance of the year in 1993 for Lord of the Night. She won a second RITA in 2000 when The Charm School was named "Favorite Book of the Year." She has also won the RITA in 2001 for Best Short Historical for The Mistress. and in 2006 for Lakeside Cottage. She has also been the recipient of the Holt Medallion, the Colorado Award of Excellnce, and the Peninsula Romance Writer's of America Blue Boa Award. Romantic Times has twice named her a Career Achievement Award winner.

Wiggs lives on a small island in Puget Sound with her husband and daughter. Her mother maintains her web page.

Discovery Series

• October Wind (1994)
• Jewel of the Sea (1994)
• Kingdom of Gold (1994)

Tudor Rose Series

• Circle in the Water (1994) revised and reissued in 2009 as At The King's Command
• Vows Made in Wine (1995) revised and reissued in 2009 as The Maidens Hand
• Dancing on Air (1996) revised reissued in 2009 as At The Queens Summons

Calhoun Chronicles

• The Charm School (1999)
• The Horsemaster's Daughter (1999)
• Halfway to Heaven (2001)
• Enchanted Afternoon (2003)
• A Summer Affair (2003)

Chicago Fire Trilogy

• The Hostage (2000)
• The Mistress (2000)
• The Firebrand (2001)

Lakeshore Chronicles

• Summer At Willow Lake (2006)
• The Winter Lodge (2007)
• Dockside (2007)
• Snow Fall at Willow Lake (2008)
• Fireside (2009)
• Lakeshore Christmas (2009)
• The Summer Hideaway (2010)
• Daisy+Logan+Julian (2011 tentative)

Novels

• Texas Wildflower (1987)
• Briar Rose (1987)
• Winds of Glory (1988)
• Moonshadow (1989)
• Lily and the Leopard (1991)
• The Raven and the Rose (1991)
• Lord of the Night (1993)
• The Mist and the Magic (1993)
• Embrace the Day (1993)
• Miranda (1996)
• Merry Christmas, Baby! (1996)
• The Lightkeeper (1998)
• The Drifter (1999)
• Husband for Hire (1999)
• The You I Never Knew (2001)
• Passing Through Paradise (2002)
• Home Before Dark (2003)
• Summer by the Sea (2004)
• The Ocean Between Us (2004)
• Lakeside Cottage (2005)
• Table for Five (2005)

Omnibus

• Purrfect Romance (1995) (with Jennifer Blake, Robin Lee Hatcher)
• This Time...Marriage (1996) (with Muriel Jensen, Janice Kaiser)
• That Summer Place (1998) (with Jill Barnett, Debbie Macomber)
• Cinderfella / Lady of the Night (2002) (with Kate Hoffmann)
• It Happened One Christmas (2003) (with Julie McBride, Nancy Warren)
• More Than Words: Volume 3 (2003) (with Tori Carrington, Karen Harper, Catherine Mann, Kasey Michaels)

Picture Books

• The Canary Who Sailed with Columbus (1989)