Instagram growth comes from Reels that strangers watch to the end and send to someone. Instagram's head, Adam Mosseri, named watch time, likes and sends as the three signals that matter most for ranking, with sends weighing a little more when the viewer doesn't follow you yet.
For a brand that already runs ads, the practical version is short: post Reels made for people who don't know you, test them as trial reels first, read sends per reach in Insights, put the winners behind ad spend, and tag every link so you can see which posts sold.
I'd judge an Instagram account by the sales its links bring in. The follower count comes along on its own.
Most Instagram growth advice is written for creators who want an audience. If you sell through paid traffic, you want something narrower. You want an account that makes your ads cheaper to test, makes a stranger who clicked an ad trust you enough to buy, and sends a few sales of its own. Those three jobs reward the same habits, and none of them needs a follower count anyone would brag about.
What Instagram ranks on
In January 2025 Mosseri started a video series on how ranking works. The first one was short and specific: "The top three signals that matter most for ranking are watch time, likes and sends." He told creators to read average watch time, likes per reach and sends per reach in their Insights, and added that "likes are slightly more important for connected content, and sends are slightly more important for unconnected content" (Social Media Today, 22 Jan 2025).
| Signal | What it tells Instagram | Weighs more with | Where you read it |
|---|---|---|---|
| Watch time | The Reel held attention | Everyone | Insights on the Reel: average watch time |
| Likes per reach | People who saw it liked it | Your followers ("connected") | Likes divided by accounts reached |
| Sends per reach | People shared it in a DM | Non-followers ("unconnected") | Shares divided by accounts reached |
"Per reach" is the part people skip. Say one Reel has 400 sends and another has 90. The first sounds better until you see it reached 200,000 accounts and the second reached 6,000. That is 0.2% against 1.5%, and the second is the idea strangers wanted to pass on. Sends per reach is the column to read first, because that's the number that decides whether people who have never heard of you get to see the next one.
You'll also run into posting-ratio rules of thumb (the 5-3-1 rule and its cousins) that say how many posts of each kind to publish. They're advice passed around by marketers. Instagram hasn't published a ratio, and the three signals above don't care about one.
Grow with Reels made for strangers
Reels are where the new viewers are. Instagram's own creator site says "Reels makes up over 50% of all time spent on Instagram" (Instagram for Creators), and since 2022 Instagram has said it is less likely to recommend reposted Reels or accounts that mostly reshare other people's work. If the goal is reach outside your followers, the post has to be a Reel, and it has to be yours.
Trial reels make this testable. Instagram rolled them out to professional accounts in December 2024: you toggle "Trial" when you post, the Reel is shown to non-followers first and stays off your grid, and after 24 hours you see its views, likes, comments and shares. Then you either post it to your profile or archive it (TechCrunch, 10 Dec 2024).
For a media buyer this is a free creative pre-test. It isn't a clean one: the people Instagram picks for a trial aren't the people your ad targeting would pick, and there's no control group. I still like it as a filter. A hook that strangers scroll past for free will usually cost you money to learn the same lesson in an ad set.
An Instagram growth routine for a busy media buyer
You don't need a content team for this. You need one idea a week and the discipline to read the numbers the same way every time.
- Pick one angle from your ads. Use the claim, objection or customer question your best ad is built on. One angle per week.
- Shoot several hooks for it. Same body, a different first two seconds in each version. The opening is what decides watch time.
- Post them as trial reels. Toggle "Trial" on each. Your followers don't see the losers.
- Read the numbers after 24 hours. Compare average watch time and sends per reach across the versions. Ignore raw views.
- Post the winner to your profile. Followers now see it, and the post can collect likes from the people who know you.
- Hand the winner to your ad account. Run it as an ad creative test next to your current control.
- Tag the link. Every link you share from Instagram carries UTM parameters, so the sale shows up against the post that sent it.
Say you shoot four hooks on Monday. On Tuesday one of them has sends per reach well above the other three and a longer average watch time. That's the one that goes to the profile and into an ad set. The other three are archived, and nobody but you ever saw them flop.
Turn organic winners into ads
The fastest Instagram growth a brand with an ad budget can buy is its own best organic post, run as an ad. The post already passed a test with strangers, and paid reach brings new people to the profile who can follow if they like what they see.
Creators speed this up. With partnership ads, a brand runs ads from a creator's handle with the creator's permission: either for one post, or for the whole account so the brand can build new ads from it. The ad carries a "Paid partnership" label, and the creator can remove the permission at any time, which pauses the running ads (Instagram Help Center). Collab posts, where a creator and the brand publish one post together, put the same Reel in front of both audiences without spend.
I'd sign account-level permission only with a written agreement that says what the brand may and may not run from that handle. The permission is broad, so the limits have to be written into the contract.
Measure Instagram growth in sales
Followers are the number Instagram shows you first, which is why it's the number most people manage. A seller on paid traffic needs a different scoreboard: the clicks from the bio link, story links and Reels, and what those clicks bought.
Two habits make that possible. First, every link you put on Instagram carries UTM parameters (utm_source=instagram, a utm_medium per surface such as bio, story or reel, and a utm_content per post), so a sale can be traced to the post that started it. Meta also adds an fbclid to links clicked on Instagram, which helps the ad side match the click. Second, purchases from your paid Instagram traffic go back to Meta from the server through the Conversions API, so ad delivery learns from the sales your pixel missed (is Meta CAPI free covers the setup).
In ElasticFunnels the Tracking Link Builder (Apps, Tools, Tracking tab) builds the tagged link and a short link to paste in your bio or a story, and the UTM Performance report (Reports, UTM Performance) shows revenue and conversions for each UTM value. That turns "the Reel did well" into "the Reel from Tuesday sold this much".
What to skip
Bought followers and engagement pods give you a number that doesn't buy anything, and they break Instagram's rules. The Community Guidelines ask accounts to stay "spam-free by not artificially collecting likes, followers, or shares", and Instagram has been removing fake likes and follows it detects since 2018. There's a quieter cost too: an account padded with followers who never watch makes every post's reach look worse, because the people Instagram shows it to first don't respond.
Follow-for-follow, mass comments and giveaway loops sit in the same bucket. They inflate the follower line on a chart and do nothing for sends per reach, which is the signal that brings strangers.
Instagram growth in Q4
October usually costs less to test in than November, when auctions crowd up around Black Friday, and a Reel that wins as a trial now is a tested creative you can scale when clicks cost more. The people who follow you in October are also a warm audience to sell to in November. The Black Friday marketing strategy post has the offer math and the email plan for that week.
Picture two brands with the same ad budget walking into November. One spent October posting whatever it had. The other ran a trial reel test every week, kept the winners and has four tested hooks ready for its Black Friday ad sets. The second brand isn't guaranteed a better month, but it starts the expensive part with fewer guesses.
- Don't build a separate content plan for Instagram. Your ads already tell you which angles sell; make Reels from those.
- A Reel that wins on organic reach has earned an ad test. It hasn't earned the full budget; let the ad account decide that.
- Never pay for followers. It costs you twice: once for the followers and again in reach you lose every time you post.
- If an Instagram link isn't tagged, treat its sales as unknown. Don't let the platform's own numbers fill the gap.
I spent nine years as CTO of a direct-response company, and the line I wrote about that time on our about page still holds: every quarter I watched revenue leak between tools. Instagram is one more place where it leaks, because the post, the click and the sale live in three different screens. Grow the account with Reels that strangers pass on, and keep the link between the post and the order intact. Then the growth shows up where it counts, in the sales report.
