Fix Plus Sign UTM Error: Replace + with %2B or Alternative

Your UTM has a + sign. GA4 shows inconsistent values across sessions.

Here's the 3-step fix to encode + correctly and restore consistent tracking.

The Problem

❌ INCONSISTENT:
?utm_campaign=google+ads

GA4 shows randomly:
- "google ads" (+ decoded as space)
- "google+ads" (+ kept as +)

One URL, two different campaign values

Quick Fix (3 Steps)

Step 1: Decide on Approach (30 seconds)

Choose one:

Option A: Encode + as %2B
→ Preserves + symbol in GA4

Option B: Replace with hyphen
→ Simpler, no encoding

Option C: Remove +
→ Shortest option

Step 2: Apply Fix (60 seconds)

Option A: Encode as %2B

❌ BEFORE:
?utm_campaign=google+ads

✅ AFTER:
?utm_campaign=google%2Bads

GA4 shows: "google+ads"

Option B: Replace with Hyphen

❌ BEFORE:
?utm_campaign=google+ads

✅ AFTER:
?utm_campaign=google-ads

GA4 shows: "google-ads"

Option C: Remove +

❌ BEFORE:
?utm_campaign=google+ads

✅ AFTER:
?utm_campaign=googleads

GA4 shows: "googleads"

Step 3: Test (30 seconds)

1. Visit fixed URL
2. Check browser console:
   new URL(location.href).searchParams.get('utm_campaign')
3. Verify consistent value
4. Check GA4 Real-Time

Done.

Automated Fix Script

function fixPlusSign(url, method = 'encode') {
    const urlObj = new URL(url);
 
    ['utm_source', 'utm_medium', 'utm_campaign', 'utm_content', 'utm_term'].forEach(key => {
        let value = urlObj.searchParams.get(key);
 
        if (value && value.includes('+')) {
            switch(method) {
                case 'encode':
                    // Encode + as %2B
                    value = value.replace(/\+/g, '%2B');
                    break;
                case 'hyphen':
                    // Replace + with -
                    value = value.replace(/\+/g, '-');
                    break;
                case 'remove':
                    // Remove + entirely
                    value = value.replace(/\+/g, '');
                    break;
            }
 
            urlObj.searchParams.set(key, value);
        }
    });
 
    return urlObj.toString();
}
 
// Usage
const broken = 'site.com?utm_campaign=google+ads';
 
console.log(fixPlusSign(broken, 'encode'));
// site.com?utm_campaign=google%2Bads
 
console.log(fixPlusSign(broken, 'hyphen'));
// site.com?utm_campaign=google-ads
 
console.log(fixPlusSign(broken, 'remove'));
// site.com?utm_campaign=googleads

Common Scenarios & Fixes

Scenario 1: Product Names

Product: C++ Programming

❌ INCONSISTENT:
utm_content=C++

✅ FIX Option 1:
utm_content=C%2B%2B
→ GA4: "C++"

✅ FIX Option 2:
utm_content=cpp
→ GA4: "cpp"

Scenario 2: Brand Names

Brand: Google+

❌ INCONSISTENT:
utm_source=google+

✅ FIX Option 1:
utm_source=google%2B
→ GA4: "google+"

✅ FIX Option 2:
utm_source=googleplus
→ GA4: "googleplus"

Scenario 3: Multiple + Symbols

Campaign: C++ for C# Developers

❌ INCONSISTENT:
utm_campaign=c++for-c#-devs

✅ FIX:
utm_campaign=cpp-for-csharp-devs
→ Simple, readable, no encoding

Bulk Fix Script

// Fix multiple URLs at once
function bulkFixPlusSign(urls, method = 'encode') {
    return urls.map(url => {
        try {
            return fixPlusSign(url, method);
        } catch (error) {
            console.error(`Failed to fix: ${"{"}{"{"}url{"}"}{"}"}}`, error);
            return url;
        }
    });
}
 
// Usage
const urls = [
    'site.com?utm_campaign=google+ads',
    'site.com?utm_source=bing+search',
    'site.com?utm_content=c++'
];
 
const fixed = bulkFixPlusSign(urls, 'encode');
console.log(fixed);
// All + encoded as %2B

Platform-Specific Application

Google Ads

Tracking Template:
`{"{"}{"{"}lpurl{"}"}{"}"}}`?utm_campaign=google%2Bads&gclid=`{"{"}{"{"}gclid{"}"}{"}"}}`
                          ↑
                    Encode + as %2B

Facebook Ads

URL Parameters:
utm_source=facebook&utm_campaign=product%2Bads
                                      ↑
                                Encode + as %2B

Email HTML

<a href="site.com?utm_campaign=product%2Bpromo&utm_source=email">
    Shop Now
</a>

Validation After Fix

function validatePlusFix(url) {
    const urlObj = new URL(url);
    const rawQuery = url.split('?')[1] || '';
 
    // Check if any unencoded + remains in UTM values
    const utmParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_content', 'utm_term'];
 
    const issues = utmParams
        .filter(param => {
            const paramPattern = new RegExp(`${"{"}{"{"}param{"}"}{"}"}}=([^&]*)`);
            const match = rawQuery.match(paramPattern);
            return match && match[1].includes('+') && !match[1].includes('%2B');
        })
        .map(param => ({
            parameter: param,
            issue: 'Contains unencoded +'
        }));
 
    return {
        valid: issues.length === 0,
        issues
    };
}
 
// Usage
const url = 'site.com?utm_campaign=google%2Bads';
const result = validatePlusFix(url);
 
if (result.valid) {
    console.log('✅ All + signs properly encoded');
} else {
    console.log('❌ Issues found:', result.issues);
}

Decision Matrix

Testing Checklist

After fixing:

✅ Visual check
   URL contains %2B (or alternative), not raw +

✅ Browser test
   new URL('url').searchParams.get('utm_campaign')
   Shows consistent value

✅ Cross-browser test
   Chrome, Firefox, Safari, Mobile
   All show same value

✅ GA4 Real-Time test
   Campaign appears with expected value
   No data fragmentation

FAQ

Should I always encode + as %2B?

If you need literal + in GA4, yes. Otherwise, consider simpler alternatives (hyphen, remove).

What if + appears multiple times?

Encode or replace ALL occurrences:

value.replace(/\+/g, '%2B') // All + → %2B

Will this break existing campaigns?

If changing mid-campaign, you'll create new campaign value in GA4. Better to fix before launch.

Can I use + for spaces?

Not recommended. Use %20 or underscores for better reliability.

Conclusion

Fix + in UTM parameters in 3 steps:

1. Choose approach: encode, replace, or remove
2. Apply fix using script or manual edit
3. Test in browser and GA4

❌ utm_campaign=google+ads (inconsistent)
✅ utm_campaign=google%2Bads (encoded)
✅ utm_campaign=google-ads (alternative)

Encode + as %2B for consistent tracking across all platforms.

Technical Reference: Plus Sign in Value Validation Rule