# On Call Plus vs On Call Extra Glucometer: Differences, Test Strips & Compatibility **By Dr Pramod kumar** · 2026-09-24 **On Call Plus** and **On Call Extra** are both blood glucose monitoring systems from ACON, but they are **different meter platforms with different compatible test strips**. This distinction is especially important when buying replacement strips. An On Call meter should not be matched to a strip simply because both products carry the **On Call** brand name. This guide compares **On Call Plus vs On Call Extra** by test-strip compatibility, blood sample size, result time, coding method, memory, averages, re-dosing and other practical features. For the complete On Call range, visit the [**On Call Glucometers & Test Strips Collection**](/collections/on-call-glucometer-test-strips) . * * * ## On Call Plus vs On Call Extra: Quick Comparison Feature On Call Plus On Call Extra Primary test Blood glucose Blood glucose Compatible test strips On Call Plus Test Strips On Call Extra Test Strips Approx. sample size 1 µL 0.4 µL Approx. test time 10 seconds 4 seconds Measurement range 20–600 mg/dL 10–600 mg/dL Coding Code-chip based system No routine manual coding Memory Up to 300 results Up to 500 results Result averages 7, 14 and 30 days 7, 14, 30, 60 and 90 days Re-dosing Follow Plus-specific instructions Supported within the manufacturer's specified short window Battery CR2032 coin cell CR2032 coin cell Alternate-site testing Follow the applicable Plus instructions Fingertip, forearm or palm where permitted by the instructions The specifications above show why Plus and Extra should be treated as **separate systems rather than two names for the same glucometer**. * * * ## Most Important Difference: Test Strip Compatibility For most customers, the single most important difference is **which test strips fit the meter**. The compatibility rule is: - **On Call Plus meter → On Call Plus Test Strips** - **On Call Extra meter → On Call Extra Test Strips** **On Call Plus and On Call Extra strips should not be treated as interchangeable.** If the front of your meter says **On Call Plus**, buy Plus strips. If the meter says **On Call Extra**, buy Extra strips. For more detailed compatibility information: - [**On Call Plus Test Strip Compatibility Guide**](/blogs/knowledge-hub/on-call-plus-test-strips-compatibility-guide) - [**On Call Extra Test Strip Compatibility Guide**](/blogs/knowledge-hub/on-call-extra-test-strips-compatibility-guide) * * * ## On Call Plus Overview **On Call Plus** is an established ACON blood glucose monitoring platform designed for use with On Call Plus Blood Glucose Test Strips. The traditional Plus system uses approximately **1 µL of blood** and provides a result in approximately **10 seconds**. It can store up to approximately **300 results** with date and time. One of the defining characteristics of the Plus system is its **code-chip based calibration**. For a complete explanation of the meter, strips, coding, pack sizes and troubleshooting, read: [**On Call Plus Glucometer & Test Strips Complete Guide →**](/blogs/knowledge-hub/on-call-plus-glucometer-test-strips-complete-guide) Or browse: [**On Call Plus Glucometers & Test Strips →**](/collections/on-call-plus-glucometer-strips) * * * ## On Call Extra Overview **On Call Extra** is a newer On Call blood glucose monitoring platform designed around faster testing, a smaller blood sample and simplified strip calibration. The standard Extra system requires approximately **0.4 µL of capillary whole blood** and provides a result in approximately **4 seconds**. It can store up to approximately **500 results** and provides 7, 14, 30, 60 and 90-day averages. The standard Extra system also uses a **no-routine-manual-coding design** and supports additional blood application within the manufacturer's specified short re-dosing window when the initial sample is insufficient. Read: [**On Call Extra Glucometer & Test Strips Complete Guide →**](/blogs/knowledge-hub/on-call-extra-glucometer-test-strips-complete-guide) Or browse: [**On Call Extra Glucometers & Test Strips →**](/collections/on-call-extra-glucometer-strips) * * * ## 1\. Blood Sample Size: Plus vs Extra The traditional On Call Plus system requires approximately **1 µL** of blood. The standard On Call Extra system requires approximately **0.4 µL**. That means Extra requires a smaller minimum sample under the applicable manufacturer specifications. Regardless of model, the sample must be applied correctly to the compatible test strip. Insufficient sample application can cause an error or prevent the test from completing. * * * ## 2\. Test Time: On Call Plus vs Extra Typical result times are: - **On Call Plus — approximately 10 seconds** - **On Call Extra — approximately 4 seconds** The countdown should begin only after the meter recognises an adequately applied sample. If the meter fails to begin testing or displays an error, consult the troubleshooting guide for your exact model rather than repeatedly using additional strips. * * * ## 3\. Coding: Code Chip vs No Routine Manual Coding This is another major operational difference between the two platforms. ### On Call Plus Coding The traditional On Call Plus system uses a **code chip associated with the test strips**. When changing strip supplies, follow the coding instructions provided with the meter and strips. For a detailed explanation: [**On Call Plus Code Chip & Coding Guide →**](/blogs/knowledge-hub/on-call-plus-code-chip-coding-guide) ### On Call Extra Coding The standard On Call Extra system does not require routine manual code-chip matching during normal use. This means users should not try to apply the older Plus code-chip procedure to an Extra meter. * * * ## 4\. Memory & Result Averages Both meters can save previous glucose readings, but their capacities differ. ### On Call Plus - Stores up to approximately 300 results - Records date and time - Provides 7, 14 and 30-day averages ### On Call Extra - Stores up to approximately 500 results - Records date and time - Provides 7, 14, 30, 60 and 90-day averages Stored readings can be useful for reviewing previous tests, but treatment decisions should be made with appropriate professional medical guidance. * * * ## 5\. Re-Dosing: An Important On Call Extra Feature The standard On Call Extra system supports **re-dosing within the manufacturer's specified short window** when the first blood application is insufficient. This can help avoid wasting a strip when the initial sample does not adequately fill the strip. However, re-dosing should not be interpreted as permission to repeatedly add blood at any time during or after a test. Read our dedicated explanation: [**On Call Extra Re-Dosing & Second Blood Sample Guide →**](/blogs/knowledge-hub/on-call-extra-redosing-second-blood-sample-guide) * * * ## 6\. On Call Plus vs Extra Test Strip Packs ### On Call Plus Test Strips Microsidd currently offers several Plus strip configurations, including: - [**On Call Plus Test Strips 50**](/products/oncall-plus-glucometer-strips-50) - [**On Call Plus Test Strips 100**](/products/oncall-plus-glucometer-strips-100) - [**On Call Plus Test Strips 200 Hospital Pack**](/products/oncall-plus-glucometer-strips-hospital-pack) - [**On Call Plus Foil-Packed Strips 50**](/products/oncall-plus-50-glucometer-strips-foil-pack) - [**On Call Plus Foil-Packed Strips 100**](/products/oncall-plus-100-glucometer-strips-foil-pack) For customers comparing quantities, read: [**On Call Plus Test Strips 50 vs 200 Pack Guide →**](/blogs/knowledge-hub/on-call-plus-strips-50-vs-200) ### On Call Extra Test Strips Current Extra options include: - [**On Call Extra Test Strips 50**](/products/oncall-extra-glucometer-strips) - [**On Call Extra Test Strips 100**](/products/oncall-extra-glucometer-strips-100) - [**On Call Extra Foil-Packed Test Strips**](/products/on-call-extra-glucometer-foiled-test-strips) * * * ## 7\. On Call Plus vs Extra Error Codes Both meters can display error messages, but **you should not assume that an error code has identical troubleshooting instructions across both models**. For example, issues can relate to: - Test-strip insertion - Used or damaged test strips - Blood sample application - Battery condition - Operating temperature - Meter electronics - Coding or calibration on applicable systems ### On Call Plus Troubleshooting For Plus messages including **E0, E1, E2, E3, E4, E5, E6, code-chip errors, HI/LO and meter problems**, use: [**On Call Plus Error Codes & Troubleshooting Guide →**](/blogs/knowledge-hub/on-call-plus-error-codes-troubleshooting-guide) ### On Call Extra Troubleshooting For Extra-specific error messages, strip problems, sample issues and re-dosing questions, use: [**On Call Extra Error Codes & Troubleshooting Guide →**](/blogs/knowledge-hub/on-call-extra-error-codes-troubleshooting-guide) * * * ## 8\. How to Identify Whether You Have Plus or Extra Before buying strips, inspect the meter itself rather than relying only on an old invoice, memory or the appearance of the strip pack. Look for the model name printed on the meter: - If the meter says **On Call Plus**, purchase Plus strips. - If the meter says **On Call Extra**, purchase Extra strips. You can also compare the model name printed on the original meter box, instruction manual or existing compatible strip packaging. If you have changed meters since your previous Microsidd order, **do not automatically reorder the same strips** without checking your current meter model. * * * ## 9\. How to Use On Call Plus and Extra Correctly While both systems follow the general process of inserting a compatible strip, obtaining a blood sample and applying it to the strip, the exact operating instructions differ. Use the guide specific to your meter: - [**How to Use On Call Plus Glucometer & Test Strips**](/blogs/knowledge-hub/how-to-use-on-call-plus-glucometer-test-strips) - [**How to Use On Call Extra Glucometer & Test Strips**](/blogs/knowledge-hub/how-to-use-on-call-extra-glucometer-test-strips) * * * ## 10\. Expiry & Storage Differences Test strips are diagnostic consumables and should be stored according to the instructions supplied with the specific product. Do not assume that storage instructions for one strip family automatically apply to another pack format. Pay particular attention to: - Printed expiry or use-by date - Required storage temperature - Protection from heat and moisture - Keeping vial-packed strips correctly closed - Keeping foil-packed strips sealed until use - Signs of damaged or contaminated packaging Read: - [**On Call Plus Test Strips Expiry & Storage Guide**](/blogs/knowledge-hub/on-call-plus-test-strips-expiry-storage-guide) - [**On Call Extra Test Strips Expiry & Storage Guide**](/blogs/knowledge-hub/on-call-extra-test-strips-expiry-storage-guide) * * * ## Which On Call Meter Fits Your Existing Strip System? For an existing user, the practical starting point is usually **compatibility with the strip system you already use**. ### If you already use On Call Plus strips Choose an appropriate On Call Plus meter configuration rather than purchasing an Extra meter and expecting your existing Plus strips to work with it. [**View On Call Plus Glucometer →**](/products/oncall-plus-glucometer) ### If you already use On Call Extra strips Use the compatible On Call Extra monitoring system. [**View On Call Extra Glucometer →**](/products/oncall-extra-glucometer) * * * ## On Call Plus or Extra for a New User? For someone who does not already own either system, the two meters can be compared by their operating characteristics rather than only by the purchase price. Relevant considerations include: - Compatible strip availability - Ongoing strip cost - Sample size - Testing speed - Coding procedure - Memory capacity - Pack sizes available - Storage and expiry requirements The appropriate choice depends on the user's requirements and the exact product configuration being purchased. This comparison is intended to explain the differences rather than replace the instructions supplied with the products. * * * ## What About On Call GK Dual? The **On Call GK Dual** should not be confused with either Plus or Extra. GK Dual is a separate platform designed to support both **blood glucose and blood β-ketone testing** using the appropriate compatible strip systems. On Call Plus strips and On Call Extra strips should therefore not be assumed to work with GK Dual. Read: [**On Call GK Dual Glucose & Ketone Monitor Complete Guide →**](/blogs/knowledge-hub/on-call-gk-dual-glucose-ketone-monitor-complete-guide) Or shop: [**On Call GK Dual Glucose & Ketone Monitor →**](/products/ketone-monitor) * * * ## Frequently Asked Questions ### Are On Call Plus and On Call Extra the same glucometer? No. They are different On Call blood glucose monitoring platforms with different specifications and compatible test-strip systems. ### Can I use On Call Plus strips in an On Call Extra meter? No. Use On Call Extra Test Strips with the On Call Extra meter. ### Can I use On Call Extra strips in an On Call Plus meter? No. Use compatible On Call Plus Test Strips with an On Call Plus meter. ### Which meter requires less blood? The standard On Call Extra system requires approximately 0.4 µL, compared with approximately 1 µL for the traditional On Call Plus system. ### Which meter gives a result faster? The standard On Call Extra system provides a result in approximately 4 seconds, while the traditional On Call Plus system takes approximately 10 seconds. ### Does On Call Plus require a code chip? The traditional On Call Plus system uses a code-chip based calibration system. Follow the coding instructions supplied with the meter and test strips. ### Does On Call Extra need coding? The standard On Call Extra system does not require routine manual coding. ### How many readings can On Call Plus store? On Call Plus can store up to approximately 300 test results with date and time. ### How many readings can On Call Extra store? The standard Extra system can store up to approximately 500 results with date and time. ### Can I add more blood to an On Call Extra strip? The manufacturer specifies a short re-dosing capability for the Extra system when the first sample is insufficient. Follow the instructions for your exact meter and test strips. ### How do I know which On Call strips to order? Check the exact model name printed on your current meter. Match **On Call Plus with Plus strips** and **On Call Extra with Extra strips**. ### Where can I buy On Call Plus and Extra products in India? Microsidd offers On Call meters, compatible test strips and selected strip pack sizes online for delivery across India, subject to availability. * * * ## Shop On Call Plus & On Call Extra - [**Shop On Call Plus Glucometers & Test Strips**](/collections/on-call-plus-glucometer-strips) - [**Shop On Call Extra Glucometers & Test Strips**](/collections/on-call-extra-glucometer-strips) - [**Shop the Complete On Call Range**](/collections/on-call-glucometer-test-strips) * * * ## Related On Call Guides - [On Call Glucometers & Test Strips Complete Guide](/blogs/knowledge-hub/on-call-glucometers-test-strips-complete-guide) - [On Call Plus Glucometer & Test Strips Complete Guide](/blogs/knowledge-hub/on-call-plus-glucometer-test-strips-complete-guide) - [On Call Extra Glucometer & Test Strips Complete Guide](/blogs/knowledge-hub/on-call-extra-glucometer-test-strips-complete-guide) - [On Call Plus Test Strip Compatibility Guide](/blogs/knowledge-hub/on-call-plus-test-strips-compatibility-guide) - [On Call Extra Test Strip Compatibility Guide](/blogs/knowledge-hub/on-call-extra-test-strips-compatibility-guide) - [On Call Plus Error Codes & Troubleshooting Guide](/blogs/knowledge-hub/on-call-plus-error-codes-troubleshooting-guide) - [On Call Extra Error Codes & Troubleshooting Guide](/blogs/knowledge-hub/on-call-extra-error-codes-troubleshooting-guide) - [On Call Extra Re-Dosing Guide](/blogs/knowledge-hub/on-call-extra-redosing-second-blood-sample-guide) * * * **Medical information notice:** This comparison provides product compatibility, specification and operating information. It does not interpret individual glucose results, diagnose a medical condition or recommend changes to treatment. Follow the instructions supplied with your specific meter and test strips and consult an appropriate healthcare professional regarding glucose targets, testing frequency, medication or treatment decisions. **Tags:** On Call Plus vs On Call Extra glucometer and test strips comparison, On-Call Extra Glucometer, On-Call Extra Glucometer Strips, On-Call Glucometers & Strips Complete Guide, On-Call plus Glucometer, On-Call Plus Glucometer Strips, On-call Plus Glucucometer and strips complete guide, On-Call Plus Trouble Shooting Guide --- > Source: [Microsidd India](https://microsidd.com/blogs/knowledge-hub/on-call-plus-vs-on-call-extra-glucometer)