How to Install FASTag: Placement, Fixing, Replacement

FASTag has become a critical part of Indian road traffic rules and regulations, with automatic payment of tolls made possible by RFID (Radio Frequency Identification) technology. It is compulsory for most vehicles to have a FASTag, and it allows for a smooth, cashless transaction at toll booths—when it is correctly installed. A misinstalled or misaligned FASTag can lead to scanning failure, payment of tolls manually, delay, and fine.

Although it’s easy, still the majority of people end up asking: Where should I attach the FASTag on the windscreen? What if it falls off? Is it safe to drive with a dark-tinted windscreen? The best part is that with little guidance, you can set up your FASTag to function right from day one with no hassle.

In our guide, we’ll show you step by step from the correct placement and installation process to diagnosing common problems and replacing a demolished tag. If you’re installing a FASTag for the first time or fixing issues with one you already have, this article includes concise, step-by-step processes and real-life tips to help you avoid costly mistakes.

Optimum placement: In the windshield on top-centre, immediately behind the rear-view mirror (IRVM). This gives the tag clear, obstruction-free line of sight to toll plaza scanners for maximum read reliability and reduced transaction failures.

Acceptable alternative: If center placement is blocked by tint bands, rain sensors, or other equipment, use the upper-left area (passenger side) of the windshield.

Do not position it in front of dark tints or ceramic designs that might suppress RFID signals and cause scanning issues.

Correct installation of your FASTag ensures smooth toll payments and eliminates frequent scanning failures. Here is a stepwise guide:

1. Clean the glass

• Clean the inside of the windshield with a glass cleaning agent or isopropyl alcohol.
• Remove all dirt, grime, and oily fingerprints from wherever you intend to attach the tag.
• Allow it to dry completely before you begin — moisture can loosen adhesion and become trapped in air bubbles.

2. Mark the spot

• Position yourself inside the car, facing the windshield.
• Ideally position the center location just behind the IRVM — that provides best visibility to RFID readers at toll gates.
• Do not place products in darkly tinted or ceramic-patterned locations because these can absorb or reflect RFID signals.

3. Peel and place

• Carefully take off the sticker backing on the back of the FASTag. Do not touch the area of glue to avoid it getting contaminated and becoming useless.
• Put the tag in the proper position and attach from the in-side of the windshield.
• Press down firmly and evenly, and eliminate air bubbles with your fingertips.

4. Do not reposition

• Do not remove and re-apply once it has been applied. It can do damage to the RFID chip or reduce adhesiveness.
• If installed incorrectly, get a replacement tag and do not reinstall it.

Why the top-center behind the IRVM?

• Line of sight: Placing the tag behind the rear-view mirror aligns it with standard toll booth scanner locations.
• Reduced glare: High center placement is less likely to reflect dashboard light or sunlight into the tag.
• Driver safety: It stays out of your line of sight while driving and doesn’t clutter the windshield.

Ceramic/tint guidance

• Modern windshields often have ceramic bands or sun-tint strips near the top.
• These are decorative or protective layers, but they can block RFID signals.
• If your IRVM area has a thick black band or tint, shift the tag slightly left or right into a clear glass zone.

Avoid placing it under dark tint films, especially aftermarket UV filters. These significantly degrade scanning performance.

Outside placement — why it’s wrong

FASTags must be stuck on the inside of the windshield. External placement exposes the tag to: Rain and moisture damage, dust, debris, and bird droppings, theft or tampering.

Also, exterior tags often fail at toll booths, causing delays and manual intervention.

Despite careful installation, you may run into occasional problems. Here’s how to fix them:

1. If scans fail:

Symptoms:

• Toll booths show “Tag Not Detected”
• Repeated scanner errors or delays in barrier lifting

Causes:

• Air bubbles between the tag and glass
• Tag placed under tint/ceramic areas
• Dirty windshield or smudged adhesive
• Tag repositioned or slightly peeled during installation

Fix:

• If the tag hasn’t been used or activated, carefully remove and reapply on clean glass.
• If the tag has been used, do not attempt to re-stick — order a replacement instead.

2. If adhesive fails:

Symptoms:

• The tag falls off or partially peels
• Sticking corners become loose over time

Causes:

• Unclean glass during install
• Humidity or heat causing adhesive breakdown
• Use of low-quality or expired adhesive

Fix:

• If the tag remains intact and unused, clean the glass and reapply using high-quality double-sided tape.
• For used/damaged tags, it’s better to request a replacement to maintain scan reliability.

3. If the tag is damaged or falls off:

What to do:

• Remove any leftover adhesive residue using a cleaner.
• If the tag is damaged or folded, block it via your FASTag issuer’s portal/app.
• Request a replacement tag to avoid misreads or dual charges at toll booths.

If your FASTag is damaged, misplaced, or expired, replacing it properly is critical to ensure smooth toll operations.

1. Remove the old tag

• Gently peel off the old FASTag from the windshield.
• Do not stack a new one over it, as this may lead to double scanning or RFID interference.
• Use a cleaner to remove all adhesive residues.

2. Block or deactivate old tag

• Log in to your FASTag issuer’s portal or mobile app.
• Deactivate or block the old tag to ensure it isn’t mistakenly charged at toll plazas.

3. Request and activate a new tag

• Place a request for a replacement through your bank/issuer (ICICI, HDFC, Airtel Payments Bank, Paytm, etc.).
• Once received, activate the new tag using your account dashboard or through customer service.

4. Install the new tag properly

• Follow the earlier step-by-step guide to place the new tag in the correct windshield position.
• Make sure only one active tag is on the vehicle.

Installing your FASTag correctly is key to avoiding scanning issues, payment failures, or unnecessary replacements. 

Here’s a more detailed breakdown of what you should and shouldn’t do when placing your FASTag:

DO:

1. Clean and dry the windshield thoroughly before installation. Wipe off the windshield with a glass cleaner or isopropyl alcohol to eliminate dust, grease, and fingerprints. A clean surface promotes good adhesion and eliminates air bubbles.
2. Place FASTag inside the vehicle, center-top of windshield, just behind interior rear-view mirror (IRVM). This area provides maximum visibility to toll plaza scanners while you are out of your line of vision while driving.
3. Press firmly over the tag across its entire face after sticking. This eliminates trapped air and gives better adhesion contact with glass.
4. Do not place the tag below tinted or ceramic finishes, for these can interfere with the RFID signal. If necessary, relocate it somewhat to an adjacent clear area.
5. If the first adhesive peels off and the tag is still unmarked, you can use issuer-approved double-sided tape to reattach it—but only as a last resort.

DON’T:

1. Do not stick the FASTag on the exterior side of the windshield. It can be damaged by weather, dirt, or tampering.
2. Avoid dark tint bands or ceramic patterns, which can block RFID signals and lead to scan failures.
3. Never reposition or reuse a used FASTag—this can damage the internal chip and reduce readability.
4. Don’t stack a new tag over an old one, as it can cause double readings.
5. Always clean off adhesive residue from any removed tag before applying a new one.

Frequently Asked Questions

1. Can I place FASTag on the dashboard or outside? 

No. FASTag should be placed inside the windshield for accurate scanning and protection from the elements.

2. What if my windshield has a heavy tint near the top? 

Use a nearby clear zone, preferably just left or right of the IRVM, avoiding thick ceramic/tinted bands. The top-left (passenger side) area is an acceptable fallback.

3. Can I reuse a removed FASTag?

Not recommended. Removing it can break the RFID antenna and weaken the adhesive. For reliability and security, order a new tag.

4. Will a small bubble matter?

Yes. Even minor air bubbles or dust under the tag can interfere with scanning. If unused, reapply carefully. If already used, consider replacing.

FASTag Placement zones and reasons

Zone	Position	Reason
Ideal zone	Top-center inside windshield, behind IRVM	Best scanner visibility, minimal interference
Alternative zone	Top-left inside windshield (passenger side)	Suitable if IRVM area is tinted or obstructed
Avoid zones	Exterior glass, over tint bands, lower areas	Susceptible to damage, poor read rates, invalid placement

FASTag Troubleshooting and fixes

Symptom	Likely Cause	Fix
Tag not scanning	Bubbles, tint, dirt interference	Reapply (if unused) or replace
Tag fell off	Weak adhesive or unclean surface	Reapply with clean tape (if tag intact), else replace
Tag damaged/torn	Mishandling or heat exposure	Remove and request new FASTag
Two tags on windshield	Multiple active RFID signals	Remove old tag and deactivate it immediately

Optional visual: 

Ceramic or tint bands are the darkened or dotted areas typically located at the top edge of a car’s windshield, just above the IRVM. They can be solid tinted strips or dotted ceramic patterns. The area above and around the IRVM often uses these bands as a shaded backdrop so the mirror, sensors, and camera modules blend in visually and stay protected from sunlight. Aftermarket tinting on the main windshield and windows is restricted to ensure road safety and visibility.

Conclusion

Proper installation of FASTag is required for hassle-free and convenient toll payments in 2025 and beyond. It is best installed for proper RFID scanning at the top-center of the windshield, just behind the rear mirror. 

It can be installed in the top-left corner location in its absence. Clean the windshield carefully just before installing the tag, without covering tinted/ceramic-coated areas, and it must be dry and free of dust. Fix FASTag firmly without air bubbles, because improper adhesion/placement can be a cause of scanning failure and toll delay.

If FASTag gets damaged, stickiness deteriorates, or delinking occurs, replace it, do not take temporary measures that lead to double charging or read failure. To replace, take out the old tag completely, clean the glass well, and go through your issuer’s re-activation procedure to avoid future issues.

For more on FASTags, keep on following Ecozaar.