Nicole Sewell (born 1981) is a former professional tennis player from Australia.
She is the daughter of former East Fremantle and Western Bulldogs footballer Jim Sewell.
| $50,000 tournaments |
| $25,000 tournaments |
| $10,000 tournaments |
| Win | 1. | 10 March 2002 | Warrnambool, Australia | Grass | Lisa McShea | 6–4, 3–6, 7–6(5) |
| Loss | 1. | 7 March 2004 | Warrnambool, Australia | Grass | Casey Dellacqua | 3–6, 6–3, 2–6 |
| Loss | 1. | 3 May 1999 | Poza Rica, Mexico | Hard | Nadia Johnston | Paula Racedo Aliénor Tricerri | 1–6, 6–7(5) |
| Loss | 2. | 17 May 1999 | Ciudad Juárez, Mexico | Hard | Kylie Hunt | Melody Falcó Joelle Schad | 6–3, 1–6, 3–6 |
| Win | 1. | 11 July 1999 | Felixstowe, United Kingdom | Grass | Leanne Baker | Victoria Davies Kate Warne-Holland | 6–1, 6–4 |
| Loss | 3. | 17 September 1999 | Frinton, United Kingdom | Grass | Leanne Baker | Natalie Grandin Nicole Rencken | 2–6, 6–3, 1–6 |
| Win | 2. | 25 June 2000 | Alkmaar, Netherlands | Clay | Mareze Joubert | Erica Krauth Vanessa Krauth | W/O |
| Loss | 4. | 23 July 2000 | Frinton, United Kingdom | Grass | Mareze Joubert | Helen Crook Victoria Davies | 2–6, 4–6 |
| Win | 3. | 13 August 2000 | Bath, United Kingdom | Clay | Mareze Joubert | Jenny Belobrajdic Ayami Takase | 6–2, 6–2 |
| Loss | 5. | 19 March 2001 | Wodonga, Australia | Grass | Beti Sekulovski | Sarah Stone Kristen van Elden | 6–3, 6–7(4), 4–6 |
| Loss | 6. | 1 April 2001 | Benalla, Australia | Grass | Beti Sekulovski | Debby Haak Jolanda Mens | 4–6, 3–6 |
| Loss | 7. | 28 October 2001 | Home Hill, Australia | Hard | Beti Sekulovski | Lisa McShea Trudi Musgrave | 5–7, 4–6 |
| Win | 4. | 23 June 2002 | Lenzerheide, Switzerland | Clay | Samantha Stosur | Leslie Butkiewicz Patty Van Acker | 6–4, 6–3 |
| Loss | 8. | 30 June 2002 | Båstad, Sweden | Clay | Samantha Stosur | Andrea Glass Dominika Luzarová | 4–6, 1–6 |
| Win | 5. | 14 July 2002 | Felixstowe, United Kingdom | Grass | Amanda Augustus | Christina Horiatopoulos Sarah Stone | 7–6(5), 6–4 |
| Win | 6. | 20 October 2002 | Mackay, Australia | Hard | Natalie Grandin | Sarah Stone Samantha Stosur | 6–3, 1–6, 6–4 |
| Loss | 9. | 2 March 2003 | Bendigo, Australia | Hard | Andrea van den Hurk | Mireille Dittmann Cindy Watson | 6–7(2), 6–3, 4–6 |
| Winner | 7. | 10 March 2003 | Benalla, Australia | Grass | Andrea van den Hurk | Rushmi Chakravarthi Ryoko Takemura | 6–3, 4–6, 6–2 |
| Winner | 8. | 24 March 2003 | Albury, Australia | Grass | Andrea van den Hurk | Chuang Chia-jung Ilke Gers | 2–6, 6–1, 6–4 |
| Loss | 10. | 13 July 2003 | Vancouver Open, Canada | Hard | Andrea van den Hurk | Amanda Augustus Mélanie Marois | 6–7(4), 4–6 |
| Winner | 9. | 28 February 2004 | Bendigo, Australia | Hard | Casey Dellacqua | Shahar Pe'er Wynne Prakusya | 6–2, 1–6, 6–2 |
| Win | 10. | 6 June 2004 | Surbiton, United Kingdom | Grass | Leanne Baker | Surina De Beer Karen Nugent | 2–6, 7–5, 7–6(6) |
| Winner | 11. | 24 July 2004 | Schenectady, United States | Hard | Casey Dellacqua | Ansley Cargill Julie Ditty | 3–6, 7–6, 6–2 |
| Loss | 11. | 1 August 2004 | Lexington, United States | Hard | Casey Dellacqua | Claire Curran Natalie Grandin | 6–7, 4–6 |
| Loss | 12. | 23 October 2004 | Rockhampton, Australia | Hard | Casey Dellacqua | Daniella Jeflea Evie Dominikovic | 5–7, 2–6 |
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