What are the most popular Substack newsletters of 2025?

1. Why “most popular” is a fragmented measurement

Substack itself does not disclose full subscriber or revenue data for individual newsletters, so any “most popular” list relies on third‑party tracking, self‑reported numbers or editorial curation; Press Gazette notes this opacity and warns revenue rankings are necessarily incomplete ^[1]. Reletter compiles a subscriber‑based top‑50 chart but it is one of several independent attempts to quantify popularity ^[2]. The result: multiple competing lists that overlap but don’t converge on a single definitive order ^{[1] [2]}.

2. Which genres dominate the top lists

Analysts find that the largest, most-followed Substacks in 2025 concentrate in U.S. news/politics, technology/business, and culture/literature. A business analysis observed that over half of top publications fell into three categories — underscoring how audiences aggregate around a few dominant beats ^[5]. Substack’s own category pages highlight strong technology, business, news and literary offerings as platform standouts ^{[6] [7] [8] [9]}.

3. Names that recur across curations and charts

Magazine features and curation lists point to specific newsletters repeatedly recommended by writers and readers: CULTURED’s roundup highlights literary and culture Substacks such as Cat Hair on the Cutting Board and others favored by writers ^[3]. Letterpal’s “Top 15” list and broader roundups similarly surface a mix of politics, culture and tech newsletters as must‑reads for 2025 ^[4]. Reletter’s chart lists the 50 largest Substacks by subscribers, giving a data‑driven snapshot of who is drawing the biggest audiences ^[2].

4. Popular ≠ highest‑earning — an important distinction

Press Gazette’s exclusive ranking of high‑earning newsletters shows that large audiences don’t always translate to the biggest subscription revenue: of big lists comparing popularity and income, only a minority appear on both, and more than 50 newsletters reportedly earn over $500,000 on Substack from subscriptions alone, though sponsorships complicate the picture ^[1]. That means “most popular” by readers and “most lucrative” by subscriptions or ads are different lists ^{[1] [5]}.

5. Independent curators and influencers shape perception

Pieces like CULTURED’s feature and the “Your favorite newsletter’s favorite newsletters” column reflect peer endorsement dynamics: writers and influencers often point readers toward specific Substacks, amplifying perceived popularity beyond raw subscriber counts ^{[3] [10]}. Independent lists (Letterpal, BecomeAWriterToday, The Design Trust) emphasize editorial taste and niche picks, which can differ from charted subscriber rankings ^{[4] [11] [12]}.

6. Tools and trackers to consult if you want current rankings

For a subscriber‑based ranking check Reletter’s Top‑50 charts; for curated, genre‑specific recommendations use Substack’s category pages (technology, business, food, literature, news) and editorial roundups like CULTURED or Letterpal ^{[2] [6] [7] [13] [9] [3] [4]}. These sources together give the best available cross‑check given Substack’s limited public data ^{[1] [2]}.

7. How to interpret these lists as a reader or researcher

Treat curated lists as pointers to quality and taste; treat charts like Reletter as the closest available measure of scale; and treat financial rankings cautiously because sponsorships and off‑platform income aren’t fully captured ^{[3] [2] [1]}. If you need an authoritative, single “most popular” list, available sources do not mention a Substack‑published definitive ranking ^[1].

8. Bottom line — who to follow to get a sense of 2025’s top Substacks

Combine a subscriber chart (Reletter) with genre pages on Substack and curated editorial roundups (CULTURED, Letterpal) to assemble a reliable picture of the platform’s leading voices in 2025; this triangulation is necessary because no single source provides full transparency on subscribers or revenue ^{[2] [6] [3] [4] [1]}.