How to Measure Event Marketing ROI

Event marketing budgets are under more scrutiny than ever. Organizers are expected to justify every dollar spent on promotion, and "it felt like it worked" doesn't cut it anymore.

The challenge isn't a lack of data — it's knowing which metrics matter, how to track them accurately, and how to translate numbers into decisions. This guide provides a practical framework for measuring event marketing ROI that you can implement for your next event.

Why Event Marketing ROI Is Hard to Measure

Before diving into solutions, it's worth understanding why measurement is challenging:

• Multiple touchpoints: An attendee might see a LinkedIn post, receive an email, click a retargeting ad, and then register. Which channel gets credit?
• Long consideration cycles: B2B event registration decisions can take weeks. The first interaction might happen months before the conversion.
• Offline influence: Word-of-mouth, hallway conversations, and manager recommendations can't be tracked digitally.
• Varying ticket values: Different registration tiers (early bird, VIP, group) have different revenue values.

These challenges are real, but they don't excuse not measuring. Even imperfect measurement is far better than no measurement.

The Event Marketing ROI Formula

At its simplest, event marketing ROI is:

ROI = (Revenue from registrations - Marketing cost) / Marketing cost x 100

For a free event, replace revenue with the estimated value of each registration (based on lead value, sponsorship per-attendee rates, or lifetime customer value).

Example calculation

• Registration revenue: 500 attendees x €500 average ticket = €250,000
• Marketing spend: €30,000 (ads, tools, content, staff time)
• ROI = (€250,000 - €30,000) / €30,000 x 100 = 733%

But this top-level number doesn't tell you which marketing channels are working. For that, you need channel-level attribution.

Key Metrics to Track

Cost per registration (CPR)

The most important metric for comparing channels. Calculate it for each marketing channel:

CPR = Channel spend / Registrations attributed to channel

Benchmark CPR varies by event type:

• Paid social (LinkedIn): €50-200 per registration
• Email marketing: €5-20 per registration
• Attendee advocacy: €15-50 per registration
• Google Ads: €30-100 per registration
• Content marketing: €15-50 per registration (amortized over time)

Attendee advocacy and email typically deliver the lowest CPR because they leverage existing relationships rather than buying attention from strangers.

Registration conversion rate

Track the conversion rate from each channel to registration:

Conversion rate = Registrations / Unique visitors from channel x 100

Healthy benchmarks:

• Direct traffic: 5-15% (these people already know your event)
• Email clicks: 8-20% (warm, targeted audience)
• Attendee referrals: 5-15% (high-trust traffic)
• Paid social: 2-5% (cold to warm audience)
• Organic social: 1-3% (broad awareness)

If a channel has high traffic but low conversion, the problem is your landing page or the traffic quality. If conversion is high but volume is low, invest more in that channel.

Attendee advocacy metrics

If you're running an attendee advocacy program (which you should be), track these specific metrics:

• Participation rate: Percentage of attendees who share (target: 20-30%)
• Shares generated: Total number of LinkedIn shares
• Estimated impressions: Potential reach of all shares combined
• Referral visits: Website visits attributed to attendee shares
• Referral registrations: New sign-ups from those visits
• Viral coefficient: New registrations per share (target: 0.1-0.5)

Tools like Attendir track these metrics automatically, so you can see exactly how many registrations your attendee sharing program drives.

Revenue per channel

Ultimately, you want to know how much revenue each channel generates:

Revenue per channel = Registrations from channel x Average ticket price

This lets you compare the revenue return of each marketing investment and make informed budget allocation decisions.

Setting Up Attribution

UTM parameters

The foundation of digital attribution is UTM tracking. Every link you share should include UTM parameters:

• utm_source: The platform (linkedin, email, google)
• utm_medium: The type of marketing (organic, paid, advocacy)
• utm_campaign: The specific campaign (spring-event-2026, early-bird)

Example for an attendee advocacy share link: https://yourevent.com/register?utm_source=linkedin&utm_medium=advocacy&utm_campaign=spring-2026

Multi-touch attribution

For B2B events with longer consideration cycles, single-touch attribution (giving all credit to the last click) is misleading. Consider:

• First-touch attribution: Credits the channel that first introduced the attendee to your event
• Last-touch attribution: Credits the channel that drove the final registration
• Linear attribution: Splits credit equally across all touchpoints
• Position-based attribution: Gives 40% credit to first touch, 40% to last touch, and 20% distributed across middle touches

For most event organizers, position-based attribution provides the most balanced view. But even simple last-touch attribution is better than no attribution at all.

Practical implementation

You don't need an enterprise analytics platform to track attribution. Here's a practical setup:

1. Google Analytics: Install on your event website with UTM tracking on all links
2. Registration platform: Ensure your registration tool captures UTM parameters
3. Spreadsheet: Create a simple dashboard that pulls registration data by UTM source/medium
4. Advocacy tool: Use Attendir or similar to track referral registrations from attendee shares

Building a Measurement Dashboard

Essential dashboard components

Create a simple dashboard (a spreadsheet works fine) that tracks weekly:

Weekly review process

Every week during your promotion period, review the dashboard and ask:

1. Which channels are driving the most registrations?
2. Which channels have the lowest CPR?
3. Is the advocacy participation rate on target?
4. Are there any channels with high spend but low return?
5. Should we reallocate budget from underperforming to outperforming channels?

This weekly cadence lets you optimize in real-time rather than doing a post-mortem when it's too late to act.

Common Measurement Mistakes

Counting impressions as success

Impressions (how many people saw your content) are a vanity metric. They measure visibility, not action. Always tie your measurement back to registrations and revenue.

Ignoring organic and earned channels

Paid channels are easy to measure because you can track every click. But organic social, attendee advocacy, and word-of-mouth often drive more registrations than paid channels. Don't undervalue them just because they're harder to track. For a full breakdown of both paid and organic tactics, see our B2B event promotion strategies guide.

Not accounting for staff time

When calculating marketing costs, include the time your team spends. If your marketing manager spends 20 hours per week on event promotion for 8 weeks, that's a real cost that should be factored into your ROI calculation.

Measuring only once

Don't wait until after the event to measure. Track weekly so you can adjust your strategy mid-campaign. The whole point of measurement is to inform decisions, not just produce a final report.

Proving ROI to Stakeholders

For budget approvals

Present your ROI case in terms stakeholders care about:

• Revenue generated vs. marketing spend
• Cost per registration compared to industry benchmarks
• Year-over-year improvement in key metrics
• Channel comparison showing which investments deliver the best returns

For advocacy programs specifically

When justifying the investment in an attendee advocacy tool:

• Show the cost of the tool vs. the registrations it generated
• Compare the CPR of advocacy to paid advertising
• Highlight the reach generated (impressions) at a fraction of the ad spend
• Note the trust advantage: peer referrals convert at higher rates than ads

Getting Started

You don't need perfect measurement from day one. Start with these basics:

1. Add UTM parameters to every link you share
2. Track registrations by source in a simple spreadsheet
3. Calculate CPR for each channel after the event
4. Compare channels and reallocate budget for next time

Each event cycle, refine your measurement. Over time, you'll build a clear picture of which marketing investments drive the most registrations per dollar spent.

Want to see exactly how many registrations your attendee advocacy program drives? Attendir provides built-in analytics for shares, impressions, and referral tracking. Start your free 7-day trial.