In the film, M (Putthipong), a university dropout low on money volunteers to take care of his terminally ill grandmother (Usha) in the hope of pocketing an inheritance.

Upon release, How to Make Millions Before Grandma Dies went viral, spurred by a social media trend where viewers posted videos of themselves crying after watching the film.

Hospitalized after a fall, Mengju is diagnosed with late-stage colorectal cancer and is predicted to die in a year; her family decides to keep the diagnosis hidden from her.

All of Mengju's children suddenly suggest methods to help care for her, which raises M's suspicions about their motive; thus, M increases his efforts as her primary carer.

Mengju also declines to move in with Kiang, and she grows closer to M. Later, she finds out Soei stole ฿200,000 hidden in her kitchen to help cover his ฿1 million gambling debt.

In December 2020, he pitched the project with a ten-page synopsis inspired by his experiences caring for his grandmother during the COVID-19 pandemic, and the fallout from her not giving her daughter or caregivers any inheritance upon her death.

[4] Producers Vanridee Pongsittisak and Jira Maligool worked with Thodsapon to make an "accessible and entertaining" screenplay compared to the initial treatment, creating a slapstick comedy about inheritance under the eventual title, featuring a grandmother and grandchild.

[4] He incorporated elements from his own life to develop the final screenplay: his maternal grandmother, who helped raise him and with whom he still lives, was diagnosed with late-stage breast cancer in 2004.

[15] Hollywood Insider's Jake Yancey stated How to Make Millions Before Grandma Dies explores gender roles, generational divides and similarities, aging, and the Thai-Chinese cultural experience.

[16] Putthipong "Billkin" Assaratanakul was cast in his debut lead film role, alongside acting debutante Usha "Taew" Seamkhum.

[20] Boonyanuch Kraithong, the director of photography for How to Make Millions Before Grandma Dies, used narrow apertures and wide shots to add depth and emphasize the characters' surroundings, in contrast to contemporary films that use a shallow focus.

[12] Pat sought to differentiate the style of How to Make Millions Before Grandma Dies to the faster-paced television series he previously worked on, which included reducing the use of music.

[19] According to Jake Yancey of Hollywood Insider, How to Make Millions Before Grandma Dies uses strict opposing colors for its characters and settings to reinforce the film's overarching themes of generational and emotional difference.

"[26] Jaithep Raroengjai was hired to compose the film's score and the soundtrack album was released digitally by GMM Music, the parent company of GDH, on September 17, 2024.

[28] How to Make Millions Before Grandma Dies saw increased worldwide popularity after videos of staff at SM Supermalls theatres in Manila handing tissues to viewers prior to screening the film went viral.

[13][30] Indonesian production company Falcon Pictures hosted the press conferences with Pat in Jakarta between May 25 and May 27 in response to the film's initial success.

[31][15] After its success in Singapore, Usha and Pat attended a ticketed fan event hosted by Golden Village in Suntec City on June 24, 2024.

[34] How to Make Millions Before Grandma Dies was marketed to voters for the 97th Academy Awards through a campaign spearheaded by the PR firm Shelter and the film's U.S. distributor Well Go USA.

How to Make Millions Before Grandma Dies began a limited release in North America on September 13, in the Netherlands on October 10, and Belgium on November 13.

[30] Shirley Low, the chief marketing officer of the Malaysian-based Golden Screen Cinemas, noted How to Make Millions Before Grandma Dies exceeded their domestic box-office expectations for a Thai film.

[64] The site's critical consensus reads, "A comedy of generational manners that blossoms into a sweet tearjerker, How to Make Millions Before Grandma Dies bets big on earnestness and hits the jackpot."

[25] In a review for Grazia Singapore, Danisha Liang praised Putthipong’s convincing portrayal and highlighted Usha's "sassy—almost feisty" presence as the film's standout.

[68] In a review for CNN Indonesia, Muhammad Hifzurahman commended the slower pace, saying "[it is] a packed story [that does not] patronize" and called the performances "sweet and very touching".

[69] Noel Wong praised How to Make Millions Before Grandma Dies for being an accurate reflection of Asian family dynamics in his review for Free Malaysia Today.

Writing for Film Threat, Alex Saveliev gave How to Make Millions Before Grandma Dies a positive review, saying it "brims with wisdom and insight" and called the comedy "acerbic and gentle".

[73] ScreenDaily's Allan Hunter further praised the direction, calling How to Make Millions Before Grandma Dies "a sentimental journey to redemption that Boonnitipat grounds in understanding and empathy", and lauded the emotional weight of Raroengjai's music.

Hunter also commended the performances of the leads, calling Putthipong "nicely understated and thoughtful" and said Usha was "remarkable" in her portrayal of "a wise and gracious figure – not a typical cuddly grandma but someone canny, realistic and determined".

[79] How to Make Millions Before Grandma Dies has been considered an atypical box office hit for Thai cinema, which has historically favored horror, action, or slapstick comedy films.

[86] In an interview with Variety, GDH associate director of business development Yanisa Hankansujarit stated this impact stretched globally, saying, "My family in the U.S. told me that their children started to come home more often [after watching the film]".

She also argued the film helped bring family audiences back to theaters in Southeast Asia following the closure of cinemas and changing theater-going habits following COVID-19.