Introduction
When it comes to securing your home, office, or bathroom, choosing the right locking mechanism can make all the difference. A both side key lock — also known as a double-cylinder deadbolt or double-sided key lock — provides keyed access from both the interior and exterior of a door. This means you need a key to unlock the door from either side, offering a significantly higher level of security compared to single-cylinder locks.
At Fab Bath Interiors, we understand that security and aesthetics go hand in hand. Whether you are renovating your bathroom, upgrading your front door, or securing a private room, selecting the right both side key lock is a decision that deserves careful thought. In this comprehensive guide, we have reviewed and compared the top both side key lock options available in 2026 — covering features, prices, pros and cons, and everything you need to make an informed purchase.
What Is a Both Side Key Lock?
A both side key lock is a locking mechanism that requires a key to operate from both sides of a door — inside and outside. Unlike a standard single-cylinder lock that has a thumb turn on the inside, a double-sided key lock eliminates the thumb turn entirely, replacing it with a key slot.
This type of lock is commonly used in:
- Front doors and back doors of homes with glass panels near the lock
- Commercial properties requiring strict access control
- Bathrooms and bedrooms needing privacy with added security
- Offices and server rooms where unauthorized access must be prevented
The primary advantage is that even if someone breaks a glass panel near the door, they cannot reach in and turn a thumb knob — they would still need the key to unlock the door.
Key Features to Look for in a Both Side Key Lock
Before diving into product reviews, here is what to evaluate when shopping for the best both side key lock:
| Feature | Why It Matters |
| Material & Finish | Determines durability and aesthetic appeal |
| Security Grade | Higher grade = better resistance to picking and forced entry |
| Cylinder Type | Pin tumbler, disc detainer, etc. — affects security level |
| Key Control | Restricted keys prevent unauthorized duplication |
| Installation Compatibility | Should fit standard door backsets (60mm or 70mm) |
| Weather Resistance | Essential for external doors |
| Brand Reputation | Reliable brands offer warranty and after-sales support |
Top Best Both Side Key Lock in 2026 – Detailed Reviews
1. Yale YD-40 Double Cylinder Deadbolt – Best Overall Both Side Key Lock
Price: ₹2,800 – ₹3,500 / $34 – $42 USD
Yale is one of the most trusted names in home security worldwide, and the YD-40 Double Cylinder Deadbolt lives up to that legacy. This both side key lock features a solid steel bolt, anti-drill, anti-pick, and anti-saw protection, making it an excellent choice for main entry doors.
Key Features:
- 6-pin cylinder for enhanced key security
- Solid brass construction with chrome or satin finish
- ANSI Grade 2 certified
- 3 keys included; anti-pick pins standard
- Easy installation with adjustable backset
Pros: Highly durable, affordable, brand reliability, good finish options Cons: Not smart-lock compatible; no keypad option
2. Godrej 3-Lever Double Cylinder Lock – Best Budget Both Side Key Lock
Price: ₹900 – ₹1,500 / $11 – $18 USD
For budget-conscious buyers who do not want to compromise on quality, the Godrej 3-Lever Double Cylinder Lock is a reliable both side key lock that has been trusted by Indian households for decades. It is ideal for interior doors, bathrooms, and lightweight security applications.
Key Features:
- 3-lever locking mechanism
- Heavy-duty steel body
- Available in multiple finishes — brass, chrome, and antique
- Fits standard door backset of 60mm
- 3 keys included
Pros: Very affordable, widely available, easy to install, trusted Indian brand Cons: Lower security rating compared to 5-lever or pin-tumbler options; not recommended for main entry doors
3. Dorma DD-88 Double Cylinder Lock – Best Premium Both Side Key Lock
Price: ₹4,500 – ₹6,000 / $54 – $72 USD
Dorma, now part of the DORMA+KABA (dormakaba) group, is a global leader in access solutions. The DD-88 is a high-security both side key lock with a precision-machined cylinder that offers exceptional resistance to forced entry, picking, and drilling. It is a top recommendation from the team at Fab Bath Interiors for main entrance doors and commercial use.
Key Features:
- 6-pin anti-pick, anti-drill cylinder
- Solid zinc alloy body with stainless steel bolt
- Modular design for easy replacement
- Security rating: EN 12209 Class 3
- 5 patented keys included with key card
Pros: Premium security, elegant European design, patented key system Cons: Premium price point; keys can be expensive to duplicate
4. ABUS EC 550 Double Cylinder Deadbolt – Best High-Security Both Side Key Lock
Price: ₹5,500 – ₹7,500 / $66 – $90 USD
ABUS is Germany’s leading security brand, and the EC 550 is a top-tier both side key lock built for environments that demand maximum security. The patented key profile and high-grade steel construction make this virtually pick-proof and drill-resistant.
Key Features:
- Patented, drill-resistant, pick-resistant cylinder
- C-Class security certification
- 6 keys included with security card
- Available in nickel silver and chrome finishes
- Suitable for doors from 35mm to 120mm
Pros: Extremely high security, great warranty, professional-grade protection Cons: Expensive; overkill for interior doors
5. Harrison 5-Lever Double Cylinder Mortise Lock – Best for Interior Doors
Price: ₹1,200 – ₹2,000 / $14 – $24 USD
Harrison is a well-known brand in the Indian market. The 5-Lever Double Cylinder Mortise Lock is a mid-range both side key lock ideal for bedrooms, bathrooms, and interior rooms where you need a secure locking solution without breaking the bank.
Key Features:
- 5-lever locking mechanism for good security
- Heavy gauge steel case
- Comes with 3 keys
- Available in SS (stainless steel) and antique brass finish
- Door thickness compatibility: 35mm–55mm
Pros: Good security for interior use, affordable, attractive finish options Cons: Not suitable as a main entry deadbolt; limited weather resistance
Both Side Key Lock Price Comparison Table 2026
| Product | Type | Security Level | Price (INR) | Price (USD) | Best For |
| Yale YD-40 Double Cylinder | Deadbolt | High | ₹2,800–₹3,500 | $34–$42 | Main Entry Doors |
| Godrej 3-Lever Double Cylinder | Mortise | Medium | ₹900–₹1,500 | $11–$18 | Interior/Budget Use |
| Dorma DD-88 Double Cylinder | Deadbolt | Very High | ₹4,500–₹6,000 | $54–$72 | Premium/Commercial |
| ABUS EC 550 Double Cylinder | Deadbolt | Extremely High | ₹5,500–₹7,500 | $66–$90 | High-Security Needs |
| Harrison 5-Lever Double Cylinder | Mortise | Medium-High | ₹1,200–₹2,000 | $14–$24 | Interior Rooms |
Both Side Key Lock Features Comparison Table
| Product | Material | Cylinder Pins | Certifications | Keys Included | Finish Options |
| Yale YD-40 | Solid Brass + Steel | 6-pin | ANSI Grade 2 | 3 | Chrome, Satin |
| Godrej 3-Lever | Steel | 3-Lever | ISI Marked | 3 | Brass, Chrome |
| Dorma DD-88 | Zinc Alloy + Steel | 6-pin | EN 12209 Class 3 | 5 (Patented) | Satin, Chrome |
| ABUS EC 550 | High-Grade Steel | 6-pin | C-Class Certified | 6 (Patented) | Nickel, Chrome |
| Harrison 5-Lever | Steel | 5-Lever | Standard | 3 | SS, Antique Brass |
Installation Guide: How to Fit a Both Side Key Lock
Installing a both side key lock is straightforward if you follow the right steps. Here is a simplified guide:
Step 1 – Measure Your Door Before purchasing, measure the door thickness (typically 35–55mm for interior, 44–55mm for exterior), the backset distance (60mm or 70mm), and the door edge width.
Step 2 – Choose the Right Lock Type For external doors, choose a deadbolt-style both side key lock. For interior doors, a mortise-type lock is usually more appropriate.
Step 3 – Mark and Drill Use the template provided with the lock to mark the hole positions. Drill the latch hole on the door edge and the cylinder holes on both faces of the door.
Step 4 – Install the Latch and Strike Plate Insert the latch bolt into the door edge hole, ensuring it operates smoothly. Fit the strike plate on the door frame.
Step 5 – Install the Cylinders Insert the double cylinders from both sides and secure with the connecting screw. Test with the key from both sides before finalizing.
Step 6 – Test and Finish Test the lock multiple times from both sides. Check that the bolt extends and retracts smoothly. Tighten all screws once satisfied.
Pro Tip: Always keep a spare key stored safely outside the home (with a trusted neighbor) when using a both side key lock, especially on bathroom or bedroom doors, to avoid being locked out.
Pros and Cons of a Both Side Key Lock
Understanding the advantages and disadvantages of a both side key lock helps you decide if it is the right choice for your specific situation.
| Pros | Cons |
| High security — no thumb turn to exploit | Risk of being locked inside without a key |
| Prevents glass-break entry near lock | Slower emergency egress |
| Ideal for doors with glass panels | Requires key discipline by all household members |
| Better key control with patented options | Slightly higher cost than single-cylinder |
| Aesthetically clean — no visible knob inside | Not allowed in some fire-safety regulations |
Safety Considerations When Using a Both Side Key Lock
While a both side key lock is excellent for security, safety must not be overlooked:
- Fire safety: In the event of a fire, you must be able to quickly unlock the door from the inside. Always keep the key nearby — never leave the home without ensuring all occupants have key access.
- Children and elderly: Households with children or elderly members should evaluate whether the key-only exit is manageable in an emergency.
- Local fire codes: Some jurisdictions restrict the use of double-cylinder locks on main exit doors. Check your local building code before installing.
- Emergency access: Inform all household members and guests about the key’s location in case of emergencies.
At Fab Bath Interiors, we always advise our clients to balance security needs with practical safety, particularly for bathroom and bedroom door applications.
How to Choose the Right Both Side Key Lock for Your Home
Choosing the perfect both side key lock depends on several personal and structural factors:
- Door location: External main entry doors need a higher-grade deadbolt; interior rooms can use a standard mortise lock.
- Budget: Godrej and Harrison offer great value under ₹2,000, while Yale and Dorma give premium quality at a moderate premium.
- Security level required: Offices and commercial spaces should invest in ABUS or Dorma-grade locks.
- Aesthetic preference: Match the finish (chrome, satin, brass) with your door hardware and interior style.
- Brand and warranty: Stick to reputed brands that offer at least a 1-year warranty and after-sales support.
The experts at Fab Bath Interiors are always available to help you find the right locking solution that suits your specific door dimensions, security needs, and design preferences.
Conclusion
A both side key lock is a smart investment for anyone who takes home or office security seriously. From budget-friendly options like the Godrej 3-Lever to premium-grade solutions like the ABUS EC 550, there is a product for every need and price point in 2026.
Our top recommendation for most homeowners is the Yale YD-40 Double Cylinder Deadbolt — it strikes the perfect balance between price, quality, and reliability. For premium buyers or commercial applications, the Dorma DD-88 or ABUS EC 550 will never disappoint.
At Fab Bath Interiors, we are committed to helping you make informed decisions about your home’s interiors and security. Explore our wide range of door hardware, bathroom fittings, and interior accessories to complete your home improvement journey with confidence.
Frequently Asked Questions (FAQs)
Q1. What is a both side key lock?
A both side key lock is a double-cylinder lock that requires a key to open the door from both the interior and exterior sides.
Q2. Is a both side key lock safe to use on interior doors?
Yes, it is safe as long as all occupants keep the key accessible at all times to avoid being locked inside.
Q3. Which is the best both side key lock for a main door in India?
The Yale YD-40 Double Cylinder Deadbolt is widely considered the best both side key lock for main doors in India due to its balance of security and price.
Q4. Can I install a both side key lock myself?
Yes, most both side key locks come with an installation template and can be fitted with standard tools, though professional installation is recommended for exterior doors.
Q5. Are both side key locks allowed in all buildings?
Not always — some fire safety codes restrict double-cylinder locks on primary exit doors, so always check local regulations before installing.