
Web Summit opens in Lisbon on November 9. Slush opens in Helsinki on November 18. Between them, they’ll put thousands of founders and investors in two cities in the last weeks before the holiday slowdown. Here’s what the organizers report about those crowds, what one VC’s records say about where its closest looks came from, and how founders and first-time fund managers can arrive with someone who already knows them.
This post covers relationships and process. It isn’t legal or investment advice.
Two Crowded Weeks in November
Web Summit runs November 9 to 12 in Lisbon. Slush runs November 18 and 19 in Helsinki. If you’re raising a round or a first fund in Europe, or you hope to meet European investors, there’s a good chance one of them is on your calendar, or on the calendar of someone who backs you.
Both events are built for meetings. Slush runs a meeting tool with tables for booked conversations. Web Summit has investor programs, meetups and a growing set of side events, including paid delegations and curated introduction sessions run by third parties. I haven’t evaluated any of those, and I’m not recommending one. They’re a sign that the organizers and the people around them know the main floor is hard to work.
What the Organizers Report
These are organizer figures, reported in the press. Treat them as marketing-adjacent, not audited counts.
- Web Summit 2025: 71,386 attendees from 157 countries, 2,725 startups and 1,857 investors, according to Tek NotÃcias, citing the organizer.
- Slush 2025: about 13,000 visitors, 6,000 startups and 3,500 investors, with about 13,000 people completing more than 23,000 meetings, according to Kauppalehti and Shifter.
Divide startups by investors and you get about 1.5 startups per investor at Web Summit and about 1.7 at Slush. That’s my arithmetic, and “investor” is each organizer’s own category, so it isn’t a precise ratio. This year’s events will look different, and I wouldn’t compare this year’s marketing numbers with last year’s reported ones.
The point is simple enough without precision. Every investor you want to meet will have plenty of founders asking for the same half hour.
What One VC’s Records Show, and What They Don’t
One careful look at deal sources comes from a single fund. In NBER Working Paper 33483 (February 2025), Jang and Kaplan studied the records of one early-stage US venture firm: 8,815 deals from August 2015 to December 2021.
- The funnel: the firm took 366 deals (4.2%) into in-depth review and invested in 114 (1.3%).
- The source mix: of the 6,581 deals with a known source, 58% were outbound, 25% inbound and 17% came from co-investors.
- The closer look: the firm scored 13.5% of co-investor referrals, 5.3% of inbound deals and 2.7% of outbound deals.
The definitions matter. Outbound means deals the firm sourced itself from accelerators, incubators, conferences and startup events. Inbound includes cold emails and referrals from the firm’s personal network, LPs and service providers. Co-investor referrals are deals another investor brought in.
So the bucket with the most deal flow, the one that includes events, got the lowest share of in-depth reviews. The smallest bucket, deals that came through another investor, got the highest.
Now the limits. This is one anonymous fund, the paper is a working paper and not peer-reviewed, and the data end in 2021. Being scored means getting an in-depth review, not getting funded. The 2.7% mixes conferences with accelerators and incubators, so it is not a conference conversion rate. And I haven’t found any data on how often a meeting at Web Summit or Slush turns into a round, so I won’t say events work or don’t work.
What the paper does suggest is narrower. At this one fund, the path a deal arrived by was linked to how closely it got looked at.
Make the Event Your Second Meeting
If someone who knows you introduces you before you fly, the meeting in Lisbon or Helsinki stops being a cold open. The investor has heard your name, knows who vouched for you and has a reason to remember you after a long day of meetings.
The people to ask are the ones who already know your work: your current investors, advisors, customers and former colleagues. Ask each one who they know who’ll be in Lisbon or Helsinki, and for one introduction. Don’t overstate it. A warm introduction gets you a conversation. It doesn’t promise a check.
Smaller rooms help too. Web Summit lists a free Ventures & builders meetup for VCs, angels and founders on November 12, which the organizer describes as a room “to skip the cold emails.” One founder who went to Slush last year while raising wrote that his most useful move was meeting the right person at a smaller side event, then booking a longer conversation for the next day. That’s one founder’s account, and he didn’t report an outcome, but the pattern is easy to copy: a short first meeting, then a real one.
Plan the Week After
The Pre-Seed to Succeed newsletter’s rule of thumb is that after November 30, venture slows to a crawl until mid-January. That’s a practitioner’s estimate, not measured data. Still, an investor you meet on November 10 or November 19 won’t have many open weeks left in the year.
So prepare the follow-up before you leave:
- A one-page update that says what you’re raising and what’s changed since your last update
- A data-room link that’s ready to send
- The name of someone who can vouch for you, who has agreed to take a call
Don’t invent urgency. If you don’t have a term sheet, don’t imply one.
What Founders Can Do Before They Board
- Ask who’s going. Write to your investors, advisors and closest customers this week. Ask who’ll be in Lisbon or Helsinki, and for one introduction each.
- Pick the smaller rooms. Choose one or two meetups or side events where your investors are likely to be. Check whether they’re paid or need an application.
- Book the second conversation. If a first meeting goes well, ask for a longer call or coffee the next day, or the following week.
- Have the follow-up ready. Update, data room and a named reference, ready before you land.
- Model, test, adjust. After the event, look at which introductions led to real conversations, and use that to plan your next one.
What GPs Can Do Before They Board
First-time fund managers are in the same crowd, from the other side. LPs and co-investors at these events meet a lot of managers.
- Start from the people who back you. Ask your portfolio founders, existing LPs and co-investors who they’d introduce you to at the event. A manager introduced by someone the LP trusts starts as a referral.
- Keep co-investors close. In the NBER study, co-investor referrals got the closest look. It’s one fund, scoring isn’t investing, and the data end in 2021, so treat it as a reason to keep those relationships warm, not as a rule.
- Write before and after. Keep a short list of 5 to 10 LPs and co-investors you already know. Send a brief note before the event and a follow-up after. That’s general practice, not a finding.
Before You Board, Who Already Knows You?
Big events put the right people in the same city. They don’t put you on anyone’s calendar. A warm path does two jobs in a crowded week: it gets you on the calendar, and it gives the investor a reason to remember you.
ConnectLab.live is a relationship discovery platform. It doesn’t predict which investors will attend an event or reply, and it gives no financial advice. It shows warm paths alongside your own contacts, so you can see who in your network sits close to the investors who fit your raise, before you get on the plane.
Connection is the currency of the 21st Century.
Before you board, who already knows you, and who do they know in that room?
- Founders: find investors who fit your raise and see who in your network can introduce you. 21-day free trial of Founder Pro: https://connectlab.live/founders
- Fund managers: claim your fund on ConnectLab: https://connectlab.live/join/funds
- Raise Smarter: daily fundraising signals: https://www.linkedin.com/newsletters/raise-smarter-7514657628552183808/
Sources
- Tek NotÃcias (Fátima Caçador), Paddy Cosgrave diz que Web Summit 26 esgotou espaço de exposição (in Portuguese) (Oct 8, 2026)
- Web Summit, Ventures & builders meetup (Nov 12, 2026 session)
- Web Summit, Join investors at Web Summit (2026)
- Slush, Why Join Slush 2025 as a Startup (2025)
- Kauppalehti, Slush 2025 figures (Nov 20, 2025)
- Shifter, Slik gikk det på Slush i 2025 (in Norwegian) (Nov 24, 2025)
- Jang & Kaplan, NBER Working Paper 33483, Venture Capital Start-up Selection (Feb 2025)
- Pre-Seed to Succeed, P2S #22: Raise Before the Freeze (Oct 12, 2026)
