10 Lessons From Building a Multi-6-Figure Newsletter Business with CJ Gustafson
How he built a newsletter that ended up making him more than his $200k+ CFO job at a tech startup.
CJ Gustafson started writing a newsletter because, as a newer CFO, he was “terrified of not remembering the playbook” he was learning at startups.
“You’re getting exposed to these secrets of running a company and making it work.”
And he did not want to let those secrets go in one ear and out the other.
So he started writing – mostly for himself. Eventually, he realized others enjoyed it, too. And slowly, the newsletter took shape.
Which is crazy, considering less than 3 years later,
now has over 66,000 subscribers to his newsletter.And has far surpassed the income he was making as a CFO at that tech company.
I wrote a deep dive on CJ’s story earlier in 2025, and you can read the full deep dive here.
But Dylan and I recently got the chance to chat with CJ about what’s happened since, and what he’s learned along the way….things I can’t always find when I write those deep dives.
But he also dropped some incredible bombs about being a creator, how to he is able to command such high rates from sponsors, and the ways he structures his time so he can write 2 newsletters and record a podcast that gets 25k listens.
And I didn’t want you to miss it, so today I’m sharing my biggest takeaways with you.
1. Making Finance Human (& Hilarious)
Now, finance, budgeting, and forecasting? Those are some dry topics. But CJ’s success has come from his unique way of keeping the content entertaining.
Mostly Metrics is not your average finance newsletter. In fact, it’s far from the norm in the space.
Between the dad jokes, pictures of his dog, and unhinged memes, CJ keeps your attention even when the topic is a little dry.
“You come for the GIFs and you stay for the CAC payback calculations.”
Take this example from what could have been a very dry post about the History of EBITDA.
The first image in the post is a screenshot of a Pharrell Williams song on Spotify, aptly titled “EBITDA.”
At the very least, CJ’s getting a chuckle out of his reader right from the beginning.
But a lot of creators are scared to put their full personality into their work. So, we asked him where this vibe comes from.
“Let your freak flag fly”
Years ago, CJ loved reading Bill Simmons when he was writing something called Grantland, which was a conversational sports blog that felt like you were shooting the sh*t with a friend.
“He made it cool to be a fan of what you’re writing about. A lot of the sports writers back then, they covered it from a grumpy angle: ‘I can’t enjoy what I’m doing.'” CJ thought that was a huge miss. “Dude, you have the best job in the world, why wouldn’t you enjoy that?”
He wanted to bring that level of excitement and personality to the finance space.
“There’s a lot of really shitty business content online.”
The content he was seeing was sterile and overly complex.
People in the finance and business space often have a scarcity complex and try to make it more and more complex so people can’t understand.
Instead, he just kept leaning into his personality quirks, and said, “I think people started to say it’s almost like I’m hanging out with CJ. And he’s not trying to say he knows everything.”
“Let your freak flag fly” was something he’d heard from Sam Parr, and he took that to heart.
Be willing to talk about things that are interesting to you, alongside things that you study pretty seriously. There’s no reason you can’t inject personality and be human about that.
It actually becomes his competitive moat because he’s not just spewing facts and figures all day; there is much more to it than that. As he says:
“You may have the recipe, but you don’t have the ingredients to copy it.”
One fun example of him injecting personality?
He told his readers that for every new 1,000 subscribers, he would buy his dog, Walter, an ice cream. This was sustainable until it wasn’t, and his newsletter was growing faster and faster.
But it added personality and humanness to his writing.

2. Mostly Monetization
CJ has over 66,000 free subscribers and a paid newsletter with over 1,000 paid subscribers.
Although he has quite a large number of paying subscribers, you might be surprised to learn that 90% of his revenue comes from his sponsorships and brand partners.
His customers are decision makers at large companies, which means his sponsors will pay CJ a lot more to get in front of them.
The brands he works with are selling products worth hundreds of thousands of dollars, so if they get just one sale, it makes sense to keep sponsoring his newsletter and podcast.
But he thinks about sponsorships very differently from a lot of creators out there.
3. Sponsorships as a Long-Term Play
When he started the newsletter, he still had a full-time job as a CFO, and didn’t have a ton of time to commit to going out and finding new sponsors. So he decided to only offer quarterly sponsorship packages.
This ended up working super well for both him and the sponsors. Because they were sticking around longer (2-3 months), he said, after the first few months, they would start to see more volume pick up and deals closing, which obviously made the partners happy and want to commit to even more spots.
If they had only sponsored one or two issues of the newsletter, they might have called it a loss and ended the relationship.
But because he’s only doing longer-term partnerships, he’s seeing a huge return for his sponsors.
The result?
CJ requiring these longer-term partnerships has led to one of his sponsors already committing to the full 2026 year as a sponsor. (It was July when he told us that!)
“I think you need to hit a CFO, not 3 times, not 5 times, not 7 times, probably 13 times they have to hear from you.”
He thinks of it like a ground game and an air game. The ground game is his newsletter, and the air game is the podcast.
“You have to surround them in a way where you build that trust over time, just to be part of the consideration set when it is time to purchase.”
4. Never discount your sponsorships
More than half of the sponsors will double up and sponsor both the podcast and newsletter.
After he said that, I off-handedly commented, “Oh so you just discount the packages if they do both.”
CJ was quick to correct me.
“I never discount anything.”
He said that as a CFO, he knows discounts are a slippery slope. The next time the customer comes to renew, they are going to expect that discount.
“Then you end up with an annuity stream if you have a continuous partner at a lower rate.”
Honestly, this was a little over my head, so I looked it up after. 🙂
Essentially, he was saying you end up with a long-term partner paying you below what your product is worth. If you discount something now, say by 20%, then over the long run, you’re losing 20% by working with that partner.
This can end up leading to resentment and even harder conversations around raising the price later.
Instead, CJ says creators could give away one send instead. That goes away afterwards and isn’t an ongoing thing they get.
Then you’re not constantly looking at this relationship with a partner who is paying you well below what you know your audience is worth.
5. Raise your prices until 50% of sponsors say no
He goes into every conversation with a new partner knowing back of the envelope math like:
How much their average transaction size is
How long their customers stick around
Based on these numbers, he can make a fair but expensive offer.
He expects 50% of sponsors to say no, and if they ask for a discount he generally knows it’s not a good fit.
CJ said that you have to stick to your guns and not give them an inch. First because it sets a precedent that you’ll do the same in the future.
But more importantly, sponsors all talk to each other, so if you discount one, the others will say “Well, you gave X brand this for $5,000, we want the same deal.”
And then you’re in a pickle.
CJ is a big fan of Scott Galloway’s saying of: “I have two prices. Really fucking expensive, or free.”
But he likes to be generous when it comes to the free stuff, though.
6. Be a generous partner
Before we jumped on the call, I was poking around his social media and noticed CJ was retweeting sponsors social posts, and commenting all over the place.
I had a feeling that this wasn’t part of the contract or anything, so I asked CJ about this.
“It’s a long-term game you want to play with long-term people.”
His sponsor could text him right now and say, “We just had this product launch and we’re trying to talk about it.”
He’ll say, “No problem, I’ll talk about it today.” Because he knows it’s important, and that kind of thing goes a long way.
Maybe he’ll comment on their post or retweet it. Or he’ll often shout his sponsors out on a podcast (as he just did haha).
But CJ’s overall ethos is one I can get behind, and one I think a lot of creators can learn from:
Be a good partner who goes the extra mile. But never compromise on price.
7. The Triple Stack Approach
If you read CJ’s deep dive, you’ll remember this. But let’s rehash it because I think it’s such a brilliant play that more creators can be doing.
This approach all started pretty early on when CJ had around 3,000 subscribers and was looking to grow the newsletter. He knew it would be awesome to get in front of the audience of specific software companies and decided to shoot his shot.
So he asked if he could write a guest post for a company called Brex.
To his surprise, they said yes.
People who are creating content for the blog of those software companies are often early in their career, or they’re doing this as an “extra” on top of all the other work they have to do in their role.
Plus, who wants to hear a brand talk about how great they are every week?
No one.
By offering to write a guest post, CJ was making their lives so much easier, and he was giving them content that was unbiased (to an extent) and more impactful.
At first, he was just trying to grow the newsletter, so he did these for free as guest posts.
Over time, he got a little extra courage and said I’ll still do this, but you have to pay me for it. He ended up charging between $1k and $2k per post.
He also threw in that he would link back to their site and repost it on his site too (if you’re reading through the lines, that means he doesn’t have to recreate content for his own site that week either).
“People are always looking for great content and if you can make someone’s life easier, they will give you the platform to do so and you may even get paid for it.”
So let’s recap:
He gets paid by the brand to write a post
The brand shares it to on their website, and often in their newsletter
CJ gets a backlink from a well-respected brand
The people who come from these posts could also end up becoming a paying subscriber to Mostly Metrics (so he could get paid twice for them)
And he didn’t have to create any extra content that week
I don’t know why I called this the Triple Stack Approach, it’s more like the Quintuple Stack Approach 🙂
The Triple Stack Approach V2
CJ no longer does these paid guest posts because he doesn’t want to cannibalize his current sponsorships.
Instead, what he’s thinking about doing is having the CEOs of brands who sponsor his reports to come on the podcast. The CEO then gets this high-quality piece of content they can share with their audience, which then grows CJs audience as well.
He’ll still get paid because they are sponsoring his stuff
He gets network effects from these high level C-Suite execs sharing out his interview
More listeners could mean more sponsorship dollars as his audience grows
It’s not as robust as the original, but it’s still effective. And I love that he’s coming up with new ways to iterate on the Triple Stack Approach.
8. Make your readers feel smart for sharing
Most of CJ’s success comes from understanding who his content is for — and why they’ll share it.
He doesn’t just think about his audience as “CFOs” because he’s found 4 distinct groups of people read his newsletter.
Aspiring CFOs who want to forward it to their boss
Current CFOs who share it with their teams
Investors who pass it to portfolio company CFOs
CEOs who want to understand their own numbers better
Then he writes something useful enough to make them look smart.
“I want to be the person they forward, because they want to look good.”
That’s what he optimizes for: the internal share. Not the like. Not the open. The moment someone hits forward and says, “You’ve got to see this.”
9. Time Management as a Creator
After all of this, I had to ask CJ how he’s writing 2 newsletters and running a podcast. His response?
“That’s my competitive advantage, though. I don’t know, how do people go to work and sit at a desk for 10 hours?”
Touche, touche.
He did give a few insightful tips on how he fits it all in.
1. He banks content
CJ said he has around 70 pieces for Mostly Metrics that are around 80% of the way complete.
So if he can’t come up with something to write that day, he’ll go back and finish something that’s already started.
2. No meetings before 1pm
Aside from taking the time to record our podcast at 11 am (thanks, CJ!), he doesn’t take calls before 1 pm, which is something he learned from
.He says he aims to get something done for either the newsletter(s) or the podcast before noon.
“Nobody is going to want to meet with me after 1pm if my writing and my podcasting sucks, that’s what I realized. So I have to take care of the main thing first.”
3. How he comes up with content ideas
This was such a simple idea but it hit me really hard. CJ said he takes his dog for a walk every morning (Walter eats a lot of ice cream, so he’s gotta stay fit somehow!) and he will try to come up with one idea on that walk.
CJ’s podcast episodes drop on Monday and Thursday, and as much as he hates hearing his own voice, he said he listens to an episode while he walks.
The goal? Come up with one idea for a post.
When he’s back at his desk, he’ll pull out the transcript of the episode to pull quotes that support the topic he came up with.
4. Start with the Title
CJ says that the easiest way to write a piece is to start with the title.
Once he has the title, he’s just off to the races. Now the goal becomes to find supporting evidence for that idea he’s just come up with.
Of course, he has a smart way to do that as well without just trying to remember times he’s mentioned that.
5. The CJ GPT
Now that he has over 200 episodes of the podcast in the bank, he’s uploaded transcripts from every episode into his own GPT.
He then asks questions about the topic he wants to write about. Like “Have I talked to anyone about roll-up strategies in private equity?”
If so, then he has the supporting evidence of the article for that title we just talked about. The beauty of this is that now he can link back to those past articles he’s written or podcast episodes he’s published.
And each piece becomes a promo for his other content, while also giving people something interesting to think about.
10. If you speak loud enough to your core audience, others will follow
This might have been my favorite part of our chat, so I’m saving it for last. Only you folks who stuck around til the end get it 🙂
I saw a post that CJ wrote called “Niches are larger than you think” that I enjoyed, and I wanted to ask him about it.
CJ initially thought he was writing for a finite audience of about 130,000 CFOs. Someone looking at his 66,000 subscribers might think he was already halfway to saturating his total addressable market. But that wasn’t the case at all.
“Everybody wants to be a part of a club. Everybody wants to be in the know,” CJ explains. “And if you’re talking about something that is like really engaging to the core people, they’re like, ‘Wow, I want to have that energy, too. I want to learn about that and feel smart,’ then I think other people get pulled into the fold.”
What he discovered through audience polls was that only about 30% of his newsletter readers were actually CFOs. The other 70% included aspiring CFOs, CEOs (15% of his audience), investors, and other business professionals who wanted to understand finance better.
But that doesn’t mean he’s going to stop positioning his content towards CFOs and expand that.
“At the end of the day, like I’m talking about running a better business. Yes, it’s written primarily from the perspective of a CFO. But a lot of people out there, regardless of their role, want to be successful in like making their company grow, making their company profitable, like helping their employees buy houses because like things went well.”
By speaking the language of CFOs authentically, CJ attracted anyone who wanted to think more strategically about business operations and metrics.
The lesson here is simple, but a hugely impactful reminder: when you create content that deeply resonates with your core audience, adjacent audiences naturally get pulled in.
These were my main takeaways from this episode, but you can watch the entire interview on YouTube, or listen to it wherever you get your podcasts.
If you enjoyed this format, please tag me on social media and let me know (Instagram, LinkedIn, Substack Notes) or reply to one of the newsletter emails. It took longer than I’d like to admit to go back and make those clips and pull out specific quotes, so I’d love to hear if it was worth it.
And tag CJ too. I want to get more guests on like this, so if they see that there are actually engaged folks out there paying attention, that will be much easier to do 🙂
I appreciate you!
This was a good read!
I really enjoyed this podcast episode.