# TLDR Review: First Alert SMI100 Smoke Alarm

*Published: 2025-05-17 | Updated: 2025-07-18 | Source: https://shopsavvy.com/reviews-tldr/first-alert-smi100-smoke-alarm*

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## Verdict

The First Alert SMI100 is a solid smoke alarm option, praised for its effective performance, convenient battery replacement, and compact design. While it offers good value and a positive user experience, potential buyers should be aware of the minor drawbacks, including less user-friendly instructions and the need for initial setup with non-functional batteries. Despite these issues, its quality construction and ease of installation make it a reliable choice for home safety needs.

**Top pro:** Battery replacement is convenient without needing to remove the unit from the ceiling.
**Top con:** Instructions have small font, making them difficult to read.

## Product: First Alert SMI100 Smoke Alarm
**Brand:** First Alert
[Compare prices and price history on ShopSavvy](https://shopsavvy.com/products/first-alert-smi100-smoke-alarm)

## Pros
- Battery replacement is convenient without needing to remove the unit from the ceiling.
- Offers a simplified installation with matching screw holes and convenient side-loading battery door.
- Loud alarm sound ensures effective alerting.
- High-quality construction and effective performance.
- Compact size and design make it easy to store in small spaces.
- Users report positive experiences leading to repurchases.
- Good value for the price with confidence in its longevity due to the 10-year battery life.

## Cons
- Instructions have small font, making them difficult to read.
- Online manual lists a different model number, causing confusion.
- Batteries included are not functional and are nearing expiration with a December 2023 date code.
- Challenging to secure the unit properly due to a tricky cover and loose screw-on design.
- The design could be more user-friendly, such as including a ratcheting base.
- The plastic locking mechanism requires a screwdriver, which is not intuitive for users.

## Pros vs Cons at a Glance

| Pros | Cons |
|------|------|
| Battery replacement is convenient without needing to remove the unit from the ceiling. | Instructions have small font, making them difficult to read. |
| Offers a simplified installation with matching screw holes and convenient side-loading battery door. | Online manual lists a different model number, causing confusion. |
| Loud alarm sound ensures effective alerting. | Batteries included are not functional and are nearing expiration with a December 2023 date code. |
| High-quality construction and effective performance. | Challenging to secure the unit properly due to a tricky cover and loose screw-on design. |
| Compact size and design make it easy to store in small spaces. | The design could be more user-friendly, such as including a ratcheting base. |
| Users report positive experiences leading to repurchases. | The plastic locking mechanism requires a screwdriver, which is not intuitive for users. |
| Good value for the price with confidence in its longevity due to the 10-year battery life. |  |

## Last Seen Prices

*Each price is the last one ShopSavvy observed, on 2025-05-17; it may have changed since.*

| Retailer | Price | Availability | Last seen |
|----------|-------|-------------|-----------|
| [Amazon](https://shopsavvy.com/api/redirect/products/e0caf891-b515-071c-5e6d-a03742e98168/offers/de03586f-2852-5c11-e75c-14cac1e7c49d?source=shopsavvy&medium=article-review-tldr) | $16.98  | In Stock | 2025-05-17 (may have changed) |

[See every retailer and the full price history on ShopSavvy](https://shopsavvy.com/products/first-alert-smi100-smoke-alarm)

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*About this review: it summarizes the professional reviews and customer ratings ShopSavvy collected for this product, alongside prices from ShopSavvy's price data (each price shows when it was last seen).*

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