| Season | Episode | Airdate | Episode Title | Story Line |
|---|
| 01.01 | 1 | 09/21/1998 | Pilot | When Grace gets a marriage proposal, Will risks their friendship by telling her what he thinks. |
| 01.02 | 2 | 09/28/1998 | A New Lease on Life | Will encourages Grace to find a place of her own while Jack's eccentricities are driving him out of his mind. |
| 01.03 | 3 | 10/05/1998 | Head Case | Tensions escalate when Grace decides to renovate the bathrooms; Will helps Jack with his résumé. |
| 01.04 | 4 | 10/12/1998 | Between a Rock and Harlin's Place | Grace redecorates Harlin's apartment. Jack creates a one-man show, "Just Jack!". |
| 01.05 | 5 | 10/26/1998 | Boo! Humbug | Will and Grace take Harlin's kids trick-or-treating. Jack and Karen go to the downtown parade. |
| 01.06 | 6 | 11/09/1998 | William, Tell | Grace becomes unraveled when she discovers that Will had a fling and didn't tell her. Karen turns to Will for legal advise. |
| 01.07 | 7 | 11/16/1998 | Where There's a Will, There's No Way | Grace blames her lack of interest in dating on her relationship with Will. Jack is audited by the IRS. |
| 01.08 | 8 | 11/30/1998 | The Buying Game | Grace seeks Will's advice on buying her studio space. Jack becomes a massage therapist. |
| 01.09 | 9 | 01/05/1999 | The Big Vent | Will and Grace eavesdrop on a real-life soap opera unfolding at the neighbor's. |
| 01.10 | 10 | 12/15/1998 | The Truth About Will and Dogs | Will develops a dog obsession after Grace brings home a puppy. |
| 01.11 | 11 | 01/12/1999 | Will on Ice | Jake and Grace surprise Will on his birthday with tickets to an ice-skating show. |
| 01.12 | 12 | 02/02/1999 | My Fair Maid-y | Will hires a cleaning lady to help Grace prepare for an upcoming decorators' contest. Meanwhile, Jack pretends to be a lawyer. |
| 01.13 | 13 | 02/09/1999 | The Unsinkable Mommy Adler | Grace gets a visit from her mother, who wreaks havoc by suggesting that she marry Will. |
| 01.14 | 14 | 02/16/1999 | Big Brother Is Coming (Part 1) | Will's estranged, older brother turns up at Jack's birthday party. |
| 01.15 | 15 | 02/23/1999 | Big Brother Is Coming (Part 2) | Grace tells Will about her romance with his brother; Karen helps Jack deal with turning 30. |
| 01.16 | 16 | 03/02/1999 | Yours, Mine or Ours | Will and Grace compete for the affections of their new neighbor when they learn that they both have a date with him. |
| 01.17 | 17 | 03/23/1999 | Secrets and Lays | Grace romances an old flame while in Vermont and tries to hide the fling from Will. |
| 01.18 | 18 | 04/08/1999 | Grace, Replaced | Will uses his new neighbor Val for his plans while Grace works; Jack is sentenced to pick up trash. |
| 01.19 | 19 | 04/22/1999 | Will Works Out | Will's embarrassed by Jack's flaming behavior while they're working out at Will's regular gym; Grace has a heart-to-heart with Karen. |
| 01.20 | 20 | 04/29/1999 | Saving Grace | A successful publicist hires Grace to decorate his house with the condition that she fixes him up with Will. |
| 01.21 | 21 | 05/06/1999 | Alley Cats | The roommates' pals don't care for competitive games; Karen saves a man using CPR. |
| 01.22 | 22 | 05/13/1999 | Object of My Rejection | Grace and Will rethink their living arrangements; Jack agrees to marry Karen's maid, Rosario. |