9 min readPublished 25 May 2025
The Ford Fiesta is one of the UK's most popular cars, and choosing the right battery depends heavily on the generation and whether it has Start/Stop. Modern Fiesta models (EcoBoost) almost exclusively use EFB batteries.
This guide covers battery sizes (063, 096, 027), technology requirements, and the best replacement options for your Fiesta.
Quick Answer
Most modern Ford Fiesta models (2012+) with Start/Stop use an EFB battery (Size 027 or 096). Older models without Start/Stop typically use a standard 063 battery. Always check for 'EFB' on your current battery label before replacing.
Common causes
- -Start/Stop stops working (battery aging)
- -Wrong battery type fitting (Standard instead of EFB)
- -BMS not reset after replacement
- -Parasitic drain from dash cams
Typical fixes
- -Replace with EFB (or upgrade to AGM)
- -Ensure BMS reset is performed
- -Check alternator output if battery dies quickly
- -Match CCA and Ah ratings to original
Ford Fiesta Battery Quick Reference
Fiesta with Start/Stop (2012+)
Likely cause: Requires EFB Battery (Size 027 or 096)
Next step: Buy EFB 60-70Ah, Reset BMS
Fiesta ST / High Spec
Likely cause: May require AGM for higher load
Next step: Check for AGM label, 096 Size common
Older Fiesta (Mk6/Mk7 non-Start/Stop)
Likely cause: Standard Lead-Acid (Size 063)
Next step: Standard 063 (40-50Ah) is sufficient
Key Fob Not Working / Dashboard Lights
Likely cause: Low voltage (often below 12.2V)
Next step: Test voltage, recharge or replace
Top 3 Battery Picks for Ford Fiesta
We've selected the best batteries based on reliability, warranty, and compatibility with Ford's Smart Charge system.
- Varta Blue Dynamic EFB (D53/D54) - Best Overall: The OEM choice for many Fords. Excellent charge acceptance for EcoBoost engines. 60-70Ah.
- Bosch S5 A08 AGM - Best Upgrade: greater cycling endurance than EFB. Ideal for Fiesta ST or models with heated seats/screens.
- Yuasa YBX5000 (Silver) - Best Value: Reliable performance for non-Start/Stop models, offering 5-year warranty peace of mind.
Ford Fiesta Battery Specs & Comparison
Choosing the right spec is critical. Do not downgrade from EFB to Standard.
- Varta Blue EFB: Tech - EFB, Size - 027/096, CCA - 560-700A, Warranty - 4 Years, Best For - Standard Start/Stop
- Bosch S4: Tech - Standard, Size - 063, CCA - 440A, Warranty - 4 Years, Best For - Older Petrol Models
- Exide Start-Stop: Tech - EFB, Size - 027, CCA - 600A, Warranty - 3 Years, Best For - Budget Start/Stop
Does the Ford Fiesta Need a BMS Reset?
Yes, modern Ford Fiestas (Mk7/Mk8, roughly 2011 onwards) equipped with the 'Smart Charge' system and a Battery Monitoring Sensor (BMS) require a reset.
Failing to reset the BMS tells the alternator the old battery is still installed, potentially leading to overcharging or undercharging the new battery, reducing its life significantly.
- Reset can often be done via dashboard button combination (e.g., rear fog + hazard light sequence)
- Can also be done via OBDII tool (Forscan)
- Crucial for Start/Stop functionality to resume quickly
See also: How to perform Ford BMS Reset
Editor's Verdict
For most UK drivers with a 1.0 EcoBoost Fiesta, the **Varta Blue Dynamic EFB** is the gold standard. It matches the factory specification perfectly and handles the frequent start-stop cycles of city driving with ease. If you have an ST or heavy electrical load, consider upgrading to an **AGM** for extra durability.
AI-Friendly Summary
- Most 2012+ Fiestas need an EFB battery, not standard.
- Common sizes are 063 (older), 027 (Start/Stop), and 096 (Diesel/ST).
- BMS Reset is required to prevent premature failure.
- The 1.0 EcoBoost engine is sensitive to battery health; replace at first sign of struggle.
Frequently Asked Questions
Can I put a standard battery in my Start/Stop Fiesta?
No. A standard battery will fail within months due to the high cycling demands and smart charging voltage. Use EFB or AGM.
How do I reset the BMS on a Ford Fiesta?
Ignition on (engine off) > Press Rear Fog button 5 times > Press Hazard button 3 times. Battery light should flash 3 times to confirm reset. (Procedure may vary by year).
What size is the Ford Fiesta battery?
It varies: Non-turbo petrols often use '063'. EcoBoosts use '027' or '096' (low height 'LB3'). Measure your battery length: 207mm (063), 242mm (027), or 278mm (096).
