Eilis is an Irish immigrant living in a family compound in Long Island, New York. She works as a bookkeeper for a local mechanic and feels intensely isolated among her tight-knit Italian American in-laws. Fiercely independent, she refuses to accept her husband's illegitimate child into her home and returns to Enniscorthy to distance herself from the crisis.

Jim is a pub owner in Enniscorthy who lives a quiet, routine-driven life above his business. He harbors deep regrets over losing Eilis twenty years prior, an event that stunted his romantic life for decades. He attempts to build a secure future through a hidden romance with Nancy, but Eilis's sudden return disrupts his plans and revives his old affections.

Nancy is a widowed mother of three who operates a chip shop converted from a market she previously ran with her late husband. She feels insecure about her appearance and social standing, often avoiding townspeople. She hopes to sell her business and build a new house outside of town to escape the constant local gossip.

Eilis's eighty-year-old mother who lives alone in Enniscorthy. She holds lingering anger toward Eilis for leaving Ireland and acts dismissively toward her daughter's life in America. She relies on daily trips into town for groceries as a way to socialize, actively rejecting modern appliances that would eliminate her need to leave the house.

Francesca is Eilis's overbearing mother-in-law who presides over the Fiorello family compound in Long Island. She prioritizes peace and family unity above all else, frequently minimizing Eilis's feelings to maintain order. She orchestrates the family's plan to adopt her son's illegitimate child, ignoring Eilis's clear boundaries.

Tony is Eilis's Italian American husband who works as a plumber in Long Island. He relies heavily on Eilis for emotional support but severely damages their marriage through a hidden affair. He avoids direct conflict, allowing his mother to handle the fallout of his infidelity rather than facing his wife's demands.

Larry and Rosella are Eilis and Tony's teenage children, raised entirely within the sheltered environment of the Fiorello family compound. Larry is highly observant and vocal about his desire for his family to remain unchanged, while Rosella is more empathetic to her mother's unhappiness.

Frank is Tony's youngest brother and a practicing lawyer. As a gay man, he shares a quiet understanding of what it feels like to be an outsider in the traditional Fiorello family. Though he initially appears to be an ally to Eilis, he ultimately aids his mother in securing Tony's new child.

George is Nancy's late husband who passed away five years before the events of the story. He previously ran the town market with Nancy. His memory heavily influences Nancy, making her feel guilty about pursuing a new romance.

Gerard is Nancy's son who works in Enniscorthy. His mother plans for him to eventually take over the family business, though she often doubts his reliability and work ethic.

Miriam is Nancy's daughter. Her impending wedding is the primary social event in her family's life and the main reason her mother keeps her new romance a secret from the public.

Martin is Eilis's brother who lives in Ireland. He provides Eilis with access to his quiet cliffside cottage in Cush, giving her a much-needed escape from their overbearing mother.

Jack is Eilis's brother who has become highly successful and wealthy. He offers Eilis financial independence by promising to buy her a house, allowing her to make choices without relying on her husband.

Shane is the reliable bartender at Jim Farrell's pub in Enniscorthy. He manages the daily operations whenever Jim leaves town, serving as a steady presence in the local community.

Collette is Shane's wife and a local resident of Enniscorthy. She acts as a friendly confidant to Jim and plays a role in the town's active network of gossip and social matchmaking.

Mr. Dakessian is a local mechanic in Long Island who services the Fiorello family's vehicles. After his daughter leaves his business, he hires Eilis to manage his bookkeeping, giving her a small measure of independence.