If you want a compact, high-efficiency solution for standard residential HVAC units where space is tight, choose Simply 18x20x1; if you need a massive supply of filters to cover a larger system or a multi-year stockpile for heavy-duty use, choose Teal Turtle 20x25x1.
• Simply 18x20x1: Its biggest strength is the advanced pleated design optimized for superior capture coverage in tight spaces, but it comes in a smaller 6-pack that requires more frequent reordering. This pick is for homeowners with standard 18x20 slots who prioritize American-made quality and specific dust control.
• Teal Turtle 20x25x1: Its biggest strength is the bulk quantity of 12 filters per case, offering exceptional longevity for large systems, though the nominal size means you must verify exact slot dimensions carefully before buying. This pick is for owners of larger forced-air systems or those looking to buy in volume to minimize future ordering trips.
• Both products are MERV 8 rated and made in the USA, but they serve different inventory and spatial needs.
The Simply 18x20x1 Air Filter is engineered for the homeowner who values precision engineering within a standard frame. With an actual size of roughly 17.81 inches by 19.81 inches, this filter is designed to fit snugly into slots labeled as 18x20x1 without forcing or leaving gaps that let unfiltered air bypass the media. The key here is the "advanced pleated technology" mentioned in its specifications. Unlike cheaper, flat pads found in big-box stores, these filters feature a higher pleat count. This isn't just a marketing flourish; more pleats mean more surface area for the airflow to pass through. In real-world terms, this translates to better airflow efficiency while trapping contaminants. You aren't just blocking dust; you are optimizing the balance between capturing particles and letting your HVAC system breathe.
Who should buy this? If you live in a home with pets, children, or anyone dealing with allergies, the Simply filter is a strong contender. It claims to trap 95% of airborne particles, which is a significant boost for indoor air quality in environments like offices, schools, or hospitals. Furthermore, the fact that it is made using 100% American components, including recycled materials, adds a layer of trust for buyers who prefer domestic manufacturing standards. The 6-pack quantity is perfect for seasonal rotation. You can change one set every three months, keeping your system clean throughout the heating and cooling seasons without overstocking your garage.
However, you should skip this product if you have a significantly larger ductwork system that requires a bigger filter footprint, or if you are the type of buyer who prefers to order once a year rather than twice. The 3-month lifespan is standard, but the 6-pack means you will need to place two orders annually to maintain continuous protection. If you forget to reorder, you risk running your system on old, clogged media, which can strain your blower motor. But for most standard homes, the trade-off of ordering slightly more frequently is worth the superior pleat density and the confidence of a filter built entirely from American parts.
We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
Updated: 2026-11-05 · 7 min read · Independent comparison
The Teal Turtle 20x25x1 Air Filter targets a completely different segment of the market: the owner of a larger forced-air system who wants convenience in bulk. The nominal size of 20x25x1 is substantial. Before you order, you absolutely must measure your existing slot or check the number printed on your current filter, as the difference between nominal and actual sizes can be tricky. Once installed correctly, this filter serves as a workhorse for furnaces, air handlers, and central air systems. The standout feature here is the unit count. A case contains twelve filters, which is double the quantity of the Simply option.
Why does this matter? Because each filter is rated for up to 90 days of use. If you swap them out quarterly, a single box of Teal Turtle filters will last you a full year. This is a game-changer for busy households or rental properties where maintenance schedules are critical. You order once, store the rest, and never worry about running out during peak allergy season or winter heating months. The filtration capability aligns well with general household needs, capturing dust, lint, pollen, and larger airborne particles. While it shares the MERV 8 rating with the Simply filter, meaning the particle capture efficiency is comparable on paper, the sheer volume of media available in the 20x25x1 format often allows for robust performance in larger systems that move more air.
This product is ideal for those who have a larger living space or a commercial-grade setup that demands a 20x25 inch footprint. It is also the smarter choice for anyone who hates the logistics of tracking inventory. Instead of remembering to buy filters in spring and fall, you buy the box in January and you are covered until the following January. Like the Simply brand, these are made in the USA, ensuring you get a quality build without relying on overseas manufacturing chains. However, if you only need a small filter for a bedroom AC unit or a tight slot, the 20x25 size simply won't fit, making this a non-starter for those with smaller HVAC units.
• Best for Standard Residential Slots → Simply 18x20x1, because its actual dimensions (17.81" x 19.81") are tailored for the common 18x20 designation.
• Best for Bulk Inventory Management → Teal Turtle 20x25x1, as the 12-pack covers a full year of changes, whereas the Simply pack requires two annual orders.
• Best for Advanced Pleat Density → Simply 18x20x1, which highlights a higher pleat count for optimized airflow and particle capture in tighter spaces.
• Best for Large Forced-Air Systems → Teal Turtle 20x25x1, designed specifically for the larger 20x25 footprint required by bigger furnaces and air handlers.
• Best for Allergy & Pet Owners → Simply 18x20x1, which explicitly lists mold, pet dander, and auto exhaust in its capture capabilities alongside its high pleat design.
• Best for Long-Term Stockpiling → Teal Turtle 20x25x1, since the 90-day rating combined with a 12-unit count provides a complete yearly supply in one shipment.
• Best for Domestic Manufacturing Support → Both products are made in the USA, so this factor is a tie, but Simply emphasizes recycled American components in its description.
• Best for Snow Removal Contexts → Neither is a snow removal tool, but both are essential for maintaining HVAC health during harsh winters when systems run constantly; Simply is better for smaller winter cabins, Teal Turtle for large heated homes.
After weighing the specifications and intended use cases, I would choose the Simply 18x20x1 for my own home if I had a standard-sized HVAC unit. The combination of higher pleat density, the explicit focus on capturing finer allergens like mold and pet dander, and the precise fit for 18x20 slots makes it the superior choice for daily air quality management. It feels like a more refined product designed for the specific needs of a typical family home.
However, if I were managing a large property or a commercial space requiring a 20x25 filter, I would immediately switch to the Teal Turtle 20x25x1. The value proposition of getting a full year's worth of filters in a single box is too compelling to ignore for large-scale operations. Ultimately, the decision rests on your physical space and your inventory habits. If you are preparing for a long, cold winter and need reliable filtration for snow removal equipment or heating systems, ensure your HVAC is running efficiently. For snow removal specifically, keeping your intake clear is vital, and a high-quality MERV 8 filter ensures your system doesn't struggle against the added load of winter operation.
Yes, both the Simply 18x20x1 and the Teal Turtle 20x25x1 are manufactured in the United States. The Simply brand specifically notes the use of 100% American components and recycled materials, while Teal Turtle confirms their filters are made in the USA for forced air systems.
Nominal size is the rough name given to the filter (like 20x25), while the actual size is the precise measurement of the physical product. For example, the Simply 18x20x1 has a nominal size of 18x20 but an actual size of 17.81"x19.81". Always measure your slot to ensure the actual size fits before ordering.
Both products are rated for up to 90 days of use. This means you should plan to change them every three months to maintain optimal airflow and filtration efficiency, especially if you have pets or live in a dusty environment.
While not designed to remove snow itself, these filters protect your HVAC system from the increased particulate load often associated with winter weather, such as road salt dust and dry air circulation. Keeping your system clean helps it run efficiently when you need heat the most.
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