| Singles | |
|---|---|
| 1998 SEAT Open | |
| Champion |  Mary Pierce |
| Runner-up |  Silvia Farina |
| Final score | 6–0, 2–0 retired |
| Draw | 30 |
| Seeds | 8 |
Amanda Coetzer was the defending champion but lost in the first round to Elena Tatarkova.
Mary Pierce won the final 6–0, 2–0 after Silvia Farina was forced to retire.
A champion seed is indicated in bold text while text in italics indicates the round in which that seed was eliminated. The top two seeds received a bye to the second round.
Nathalie Tauziat (semifinals) Mary Pierce (champion)
Irina Spîrlea (quarterfinals)
Amanda Coetzer (first round)
Ai Sugiyama (quarterfinals)
Anke Huber (quarterfinals)
Iva Majoli (second round)
Henrieta Nagyová (first round)| Final | ||||||
| Silvia Farina | 0 | 0 | r | |||
| 2 | Mary Pierce | 6 | 2 | |||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 1 | N Tauziat | 6 | 6 | ||||||||||||||||||||||||
 V Ruano Pascual | 4 | 2 | Q |  S Plischke | 2 | 4 | |||||||||||||||||||||
| Q | S Plischke | 6 | 6 | 1 | N Tauziat | 6 | 6 | ||||||||||||||||||||
| A Mauresmo | 6 | 6 | 6 | A Huber | 3 | 3 | |||||||||||||||||||||
 C Black | 3 | 4 | A Mauresmo | 3 | 7 | 1 | |||||||||||||||||||||
 R Kuti-Kis | 5 | 2 | 6 | A Huber | 6 | 6 | 6 | ||||||||||||||||||||
| 6 | A Huber | 7 | 6 | 1 | N Tauziat | 2 | 6 | 3 | |||||||||||||||||||
| 3 | I Spîrlea | 6 | 6 | S Farina | 6 | 2 | 6 | ||||||||||||||||||||
| WC |  M Oremans | 3 | 1 | 3 | I Spîrlea | 6 | 6 | ||||||||||||||||||||
| M Serna | 7 | 4 | 0 |  S Appelmans | 3 | 1 | |||||||||||||||||||||
| S Appelmans | 5 | 6 | 6 | 3 | I Spîrlea | 4 | 6 | 3 | |||||||||||||||||||
| J Kruger | 3 | 3 | S Farina | 6 | 4 | 6 | |||||||||||||||||||||
| WC |  A Kremer | 6 | 6 | WC | A Kremer | 4 | 2 | ||||||||||||||||||||
| S Farina | 6 | 6 | S Farina | 6 | 6 | ||||||||||||||||||||||
| 8 | H Nagyová | 3 | 3 | ||||||||||||||||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 7 | I Majoli | 6 | 6 | ||||||||||||||||||||||||
| R Dragomir | 2 | 4 | 7 | I Majoli | 2 | 4 | |||||||||||||||||||||
 M Grzybowska | 6 | 1 | r | Q |  E Kulikovskaya | 6 | 6 | ||||||||||||||||||||
| Q | E Kulikovskaya | 1 | 5 | Q | E Kulikovskaya | 2 | 0 | ||||||||||||||||||||
| E Likhovtseva | 6 | 6 | E Likhovtseva | 6 | 6 | ||||||||||||||||||||||
| Q | R Grande | 1 | 1 | E Likhovtseva | 6 | 6 | |||||||||||||||||||||
 E Tatarkova | 6 | 6 | E Tatarkova | 2 | 1 | ||||||||||||||||||||||
| 4 | A Coetzer | 1 | 4 | E Likhovtseva | 1 | 5 | |||||||||||||||||||||
| 5 | A Sugiyama | 6 | 3 | 6 | 2 | M Pierce | 6 | 7 | |||||||||||||||||||
| Q |  K Hrdličková | 3 | 6 | 1 | 5 | A Sugiyama | 6 | 4 | 6 | ||||||||||||||||||
| A Fusai | 1 | 4 | B Schett | 4 | 6 | 4 | |||||||||||||||||||||
| B Schett | 6 | 6 | 5 | A Sugiyama | 3 | 2 | |||||||||||||||||||||
| A-G Sidot | 3 | 1 | 2 | M Pierce | 6 | 6 | |||||||||||||||||||||
| S Pitkowski | 6 | 6 | S Pitkowski | 6 | 1 | 3 | |||||||||||||||||||||
| 2 | M Pierce | 4 | 6 | 6 | |||||||||||||||||||||||
Monica Seles was the reigning champion but did not compete that year.
Mary Pierce was the defending champion but lost in the third round to Amy Frazier.
Mary Pierce was the defending champion but lost in the quarterfinals to Kimberly Po.
Irina Spîrlea was the defending champion but did not compete that year.
Conchita Martínez was the four-time defending champion but lost in the final to Mary Pierce, 6–4, 6–0.
Steffi Graf was the defending champion but lost in the quarterfinals to Amanda Coetzer.
Martina Hingis was the defending champion and won in the final 6–0, 6–2 against Conchita Martínez.
Monica Seles was the defending champion and won in the final 6–2, 6–4 against Anke Huber.
Steffi Graf was the defending champion but did not compete that year.
Steffi Graf was the defending champion but did not compete that year.
Steffi Graf was the defending champion but did not compete that year.
Arantxa Sánchez Vicario was the defending champion and won in the final 6–1, 6–4 against Gabriela Sabatini.
Manuela Maleeva-Fragniere and Leila Meskhi were the defending champions. Maleeva-Fragniere retired from tennis earlier that year, but only Meskhi competed that year with Eugenia Maniokova.
Martina Hingis was the defending champion but did not compete that year.
Lindsay Davenport was the defending champion but lost in the semifinals to Mary Pierce.
Mary Pierce was the defending champion but lost in the third round to Mirjana Lučić.
The 1998 du Maurier Open women's singles was the women's singles event of the one hundred and ninth edition of the Canadian Open; a WTA Tier I tournament and the most prestigious women's tennis tournament held in Canada. Monica Seles was the defending champion and won in the final 6–3, 6–2 against Arantxa Sánchez Vicario.
Lindsay Davenport was the defending champion and won in the final 7–5, 6–3 against Venus Williams.
Serena Williams was the defending champion, but lost in the quarterfinals to Mary Pierce.
Martina Hingis and Mary Pierce were the defending champions, but neither participated in this tournament.