Best Cement Block for 4×4 Post: 10 Deck Blocks and Post Bases Compared by Load and Fit

The best cement block for 4×4 post work depends on how your post meets the ground. Some posts sit on a deck block that rests on gravel. Others bolt to a cured slab, or drop into a bracket set in wet concrete.

Classic poured concrete blocks are heavy, so this list covers the lighter plastic deck blocks that replace them, plus steel post bases built to anchor a 4×4 to concrete. We compared 10 options by type, post fit, listed load limit and pack size, using only what each listing states.

Check your local building code before you start. Many codes set rules for footing depth and for which decks can float on surface blocks.

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On this page

1. Compare 4×4 Post Blocks by Type, Post Fit, Load and Pack Size
2. Detailed Reviews: Best Cement Blocks and Bases for 4×4 Posts
3. Match the Block to the Way Your Post Meets the Ground
4. Keep the Post End Off the Concrete
5. How to Choose a Cement Block for a 4×4 Post
6. Which Cement Block for a 4×4 Post Should You Choose?
7. Frequently Asked Questions
8. Final Verdict

Compare 4×4 Post Blocks by Type, Post Fit, Load and Pack Size

Detailed Reviews: Best Cement Blocks and Bases for 4×4 Posts

1. CAMO Block Heavy Duty Deck Block Foundation Support Base (8 Pack) (Best overall deck block)

• 1,800 lbsListed load
• 2.16 lbsBlock weight
• 15.75 x 15.75 x 3.5 inSize
• 30 yearsWarranty

Best for: DIY builders setting a ground level deck, landing or shed on 4×4 posts who want to carry blocks without help

Why it ranks #1: It pairs the highest load figure among the post-slotted blocks with a wide 15.75 in footprint and a 30-year warranty, which edges out the BULLKE Handi Block.

The CAMO Block from National Nail is a molded deck block that takes the place of a heavy cement block under a 4×4 post. The listing gives each block a 1,800 lb load limit and a 15.75 x 15.75 in base that stands 3.5 in tall. National Nail says one block weighs 2.16 lbs, about 18 times lighter than a concrete deck block.

The top accepts 4×4 and 6×6 posts, 2×4, 2×6 and 2×8 wood joists, and 2 in metal joists. The slots are molded to standard lumber sizes, so you do not chip out openings by hand. Blocks nest together in a stack, which helps when you haul all 8 of them in a small car.

Skip it if you need a post fixed to an existing slab; the AXWHYS 4×4 Post Base 4 Pk bolts straight to cured concrete.

2. BULLKE USA Made Foundation Handi Block Deck Support (Best recycled plastic block)

• 1,750 lbsListed load
• 3.54 x 3.54 inPost fit
• 1.38 to 1.61 inJoist fit
• 100%Recycled plastic

Best for: builders who want a USA made, UV resistant block for a shed, raised walkway or small deck

Why it ranks #2: Its load figure sits only 50 lbs under the CAMO Deck Block 8 Pack, but the listing gives no block size or weight, so the CAMO wins on detail.

BULLKE makes the Handi Block in the USA from 100% recycled plastic, and the listing says it resists UV, cracking and fading. Each block takes a 3.54 x 3.54 in post, which is a standard 4×4, and joists from 1.38 to 1.61 in thick, which covers 2×4, 2×6 and 2×8 lumber.

BULLKE lists a 1,750 lb load per block. That puts it close to the CAMO Deck Block 8 Pack and just above the Myard Deck Block 2 Pack. The listing does not state the block footprint, height or weight, or how many come in a pack, so check the product page before you count out a full layout.

Skip it if you want a known block footprint to plan spacing; the CAMO Deck Block 8 Pack lists 15.75 x 15.75 in.

3. Myard 2-Pack Deck Foundation Block PNP153544 (Best for anchoring to the ground)

• 1,700 lbsListed load
• 2 lbsBlock weight
• 4 cornerAnchor holes
• 5 topScrew holes

Best for: small projects like a landing, BBQ pad or dog shelter where you want to stake each block down

Why it ranks #3: It is the only block here with holes for ground anchors and post screws, though its 1,700 lb load trails the BULLKE Handi Block.

Myard builds this deck foundation block from new Polyamide 66 nylon with glass fiber and an anti-UV additive. Each block weighs 2 lbs, and Myard compares that with about 50 lbs for a concrete block. The listing gives a 1,700 lb load per block and a footing pad 12 in wide.

A four-way recess takes 2×4 joists at an actual 1.5 x 3.5 in, and the center takes a 4×4 post at 3.5 x 3.5 in or a 100 x 100 mm post. Five holes on top let you screw the post or joist in place. Four corner holes take ground anchors so the block cannot slide.

Skip it if you need many footings for a full deck; the CAMO Deck Block 8 Pack comes 8 to a pack.

4. TPSHKE 4 Pack U Shape Post Anchor for Concrete, 11 Gauge Galvanized (Thickest wet-set anchor)

• 3 mm (11 gauge)Steel thickness
• 3.6 x 3.6 inInner size
• M10 x 120 mmBolts (4)
• M6 x 40 mmScrews (32)

Best for: pergola or fence builders pouring new concrete footings who want the post held off the concrete

Why it ranks #4: Its 3 mm steel is thicker than the 13 gauge AXWHYS 4×4 Post Base 4 Pk and the 2 mm EONECROSS Adjustable Base, and it beats the Nrspp Wet Post Anchor 4 Pk by adding through bolts.

TPSHKE makes this U-shaped post anchor from 3 mm thick galvanized steel, listed as 11 gauge, with a black powder coat over it. You push the anchor into wet concrete and let it cure for a permanent mount. An H-shaped base with two cross bars helps lock it into the pour.

The inner size is 3.6 x 3.6 in, and TPSHKE says to trim the post to that size. A planed 4×4 at 3.5 in will slide in with a small gap instead. The pack holds 4 anchors, 32 M6 x 40 mm hex screws and 4 M10 x 120 mm bolts with nuts. Follow the concrete bag label, since wet cement can burn skin.

Skip it if your slab is already cured; the MIAOXY Galvanized Base 6 Pk surface mounts with included hardware.

5. AXWHYS 4×4 Post Base 4 Pcs, 13GA Black Powder Coated Steel (Most hardware included)

• 13 gaugeSteel
• 3.6 x 3.6 inInner size
• 24Concrete anchors
• 32Post screws

Best for: anyone fixing 4×4 posts to a finished patio slab or wood deck for a pergola, railing or mailbox

Why it ranks #5: It includes anchors for concrete and screws for wood, which the EONECROSS Adjustable Base and MIAOXY Galvanized Base 6 Pk match only in part, though its steel is thinner than the TPSHKE U Post Anchor 4 Pk.

The AXWHYS post base is solid 13 gauge steel with a black powder coat. It mounts on top of a cured slab or a wood deck, so you skip pouring a new footing. A partition in the bottom keeps the post end off the ground, and a small center box helps hold the post square.

The kit is the most complete in this guide. You get 24 expansion anchors for concrete, 24 socket head wood screws for wood floors, 32 Phillips self-tapping screws for the post and a wrench. The inner size is 3.6 x 3.6 in, which gives a planed 3.5 in 4×4 a little play.

Skip it if you are setting posts in a new pour; the TPSHKE U Post Anchor 4 Pk goes into wet concrete.

6. BULLKE USA Made Pier Pads 10 in Deck Blocks (10-Pack) (Highest listed load)

• 18,000 lbsListed load
• 10.375 inWidth
• 1.10 inHeight
• 10Pads per pack

Best for: floating deck or shed bases on firm, level ground where you want a low pad under each post or beam

Why it ranks #6: Its load figure is far above every other block, but the listing does not describe a post socket, which keeps it behind the slotted CAMO Deck Block 8 Pack, BULLKE Handi Block and Myard Deck Block 2 Pack.

BULLKE Pier Pads measure 10.375 in across and 1.10 in tall, made in the USA from 100% recycled plastic. They sit on the ground with no digging and lift joists off damp soil, which the listing says helps protect the deck from moisture and erosion.

BULLKE lists a load of up to 18,000 lbs per pad. That is about ten times the 1,750 lbs given for the company’s own BULLKE Handi Block, and the listing does not explain the difference. The listing also does not describe a 4×4 post slot, so plan on a post base or bracket to keep the post from sliding.

Skip it if you need the post locked in place; the CAMO Deck Block 8 Pack has molded 4×4 slots.

7. Nrspp 4 Pcs 4×4 Wet Concrete Fence Post Anchor, U Shape (Best for fence and railing posts)

• 14 inTotal height
• 8 inDepth in concrete
• 6 inAbove concrete
• 48Screws included

Best for: fence, handrail and mailbox posts set in new concrete where the wood should stay clear of the footing

Why it ranks #7: Its 8 in embed and 6 in rise suit fences, but it uses screws only, while the TPSHKE U Post Anchor 4 Pk adds through bolts.

The Nrspp anchor is a U-shaped bracket of Q235B steel with a black powder coat. It stands 14 in tall: 8 in goes into the wet concrete, and 6 in rises above it to hold the post. The opening is 3.6 x 3.6 in, sized for a standard 4×4 wood post.

You set the rod into the wet concrete until it sits level with the surface, then let it cure. After that you slide in the post and drive screws through the pre-drilled holes on both sides. The pack has 4 brackets and 48 screws. Wear gloves and follow the concrete bag label.

Skip it if you are mounting to an existing patio; the AXWHYS 4×4 Post Base 4 Pk bolts onto cured concrete.

8. EONECROSS 10PCS 4×4 Post Base for Concrete Adjustable, Black E-Coated (Biggest pack of post bases)

• 10Bases per pack
• 1 inStandoff
• 2 mmSteel thickness
• 3.5 x 3.5 inInner size

Best for: pergola, porch or gazebo builds with many posts on a slab that is not quite level

Why it ranks #8: It gives the most bases per pack and an adjustable level, though its 2 mm steel is thinner than the 3 mm TPSHKE U Post Anchor 4 Pk.

EONECROSS packs 10 post bases in this kit, the most of any steel base in this guide. Each one is steel with galvanizing under a black e-coat for two layers of rust protection. The inner size is 3.5 x 3.5 in, which matches a planed 4×4 more closely than the 3.6 in bases.

A 1 in standoff holds the post end above the concrete to cut down on rot and insect damage. The listing says the base has an adjustable level design, which helps when a slab has a slight slope. Expansion anchors and self-tapping screws come in the box, plus an instruction manual.

Skip it if you need only a few posts; the MIAOXY Galvanized Base 6 Pk comes in a smaller 6 pack.

9. MIAOXY 4×4 Post Base for Concrete, Heavy Duty Galvanized Steel, 6 Pack (Best galvanized surface mount)

• 6Bases per pack
• 1 inStandoff
• 3.5 x 3.5 inPost fit
• GalvanizedFinish

Best for: deck, porch and fence repairs where you replace a few rotted posts on an existing slab

Why it ranks #9: It matches the EONECROSS Adjustable Base on standoff and fit, but the listing gives no steel thickness and no adjustment.

The MIAOXY base is galvanized steel sized for a nominal 4×4 with an actual 3.5 x 3.5 in face. MIAOXY asks you to measure your post before you buy, which is good advice for any base in this list. The galvanized finish is there to resist rust from rain and damp.

The 1 in raised standoff keeps the post bottom off the concrete for airflow and less water contact. Pre-drilled holes and matching hardware let you surface mount on cured concrete or another solid surface. The listing calls the steel thick but does not give a gauge, and the pack holds 6 bases.

Skip it if your slab slopes; the EONECROSS Adjustable Base has an adjustable level design.

10. Bullke USA Made Original Round Foundation Block (10-Pack) (Lowest profile round block)

• 10 inDiameter
• 1 7/8 inHeight
• 10Blocks per pack
• 100%Recycled plastic

Best for: floating sheds and low platforms on carefully leveled gravel

Why it ranks #10: It is a simple, fixed-height base with no listed load or post size, so it ranks last for 4×4 work.

The Bullke Original Round Foundation Block, sold as a Handi Block, is 10 in across and 1 7/8 in tall. It is made in the USA from 100% recycled plastic. Bullke lists uses such as floating piers, post and beam supports and shed platforms, and says the round shape adds stability.

The height is fixed, so Bullke says to level the gravel or soil under each block before you set it. The listing calls the load capacity high but gives no number, and it does not state a 4×4 post fit. Use it under a beam, or pair it with a post base.

Skip it if you need a known load limit; the CAMO Deck Block 8 Pack lists 1,800 lbs per block.

Match the Block to the Way Your Post Meets the Ground

The most common mistake is buying the wrong type of base. A 4×4 post can meet concrete in three ways, and each one needs a different product.

A deck block sits on top of gravel or firm soil and holds the post in a slot. The CAMO Deck Block 8 Pack, BULLKE Handi Block and Myard Deck Block 2 Pack work this way, with listed loads from 1,700 to 1,800 lbs. These suit floating decks, sheds and landings.

A wet-set anchor goes into fresh concrete before it cures. The TPSHKE U Post Anchor 4 Pk and Nrspp Wet Post Anchor 4 Pk are U-shaped brackets for new footings.

A surface base bolts onto a slab that has already cured. The AXWHYS 4×4 Post Base 4 Pk, EONECROSS Adjustable Base and MIAOXY Galvanized Base 6 Pk use expansion anchors or screws for this job.

Rule of thumb: if you have no slab and are not pouring concrete, you want a deck block. If you have a slab, you want a surface base.

Keep the Post End Off the Concrete

Wood that sits flat on concrete wicks up water and rots from the bottom. Look for a gap of about 1 in between the end grain and the surface.

The EONECROSS Adjustable Base and MIAOXY Galvanized Base 6 Pk both list a 1 in standoff. The AXWHYS 4×4 Post Base 4 Pk uses a bottom partition to keep the post separate from the ground. The Nrspp Wet Post Anchor 4 Pk goes further and holds the post 6 in above the concrete, which suits fence posts in wet lawns.

Plastic deck blocks such as the CAMO Deck Block 8 Pack lift the frame a little off the soil, and BULLKE says its BULLKE 10 in Pier Pads creates a gap that shields joists from moisture. Either way, use ground contact treated lumber for posts near soil, and seal any cut end before it goes into a base.

How to Choose a Cement Block for a 4×4 Post

Load limit

Plastic blocks in this list run from 1,700 lbs for the Myard Deck Block 2 Pack to 1,800 lbs for the CAMO Deck Block 8 Pack. The BULLKE 10 in Pier Pads lists 18,000 lbs, far above the rest. Add up the weight of your deck, people and snow, then divide by the number of blocks. Keep each block well under its listed limit.

Post fit

A planed 4×4 measures 3.5 x 3.5 in. The EONECROSS Adjustable Base and MIAOXY Galvanized Base 6 Pk fit that size. The TPSHKE U Post Anchor 4 Pk, AXWHYS 4×4 Post Base 4 Pk and Nrspp Wet Post Anchor 4 Pk open to 3.6 in, which suits rough or swollen posts but leaves a little play on a planed post. Measure your posts before you buy.

Steel thickness

For steel bases, thicker steel resists bending. The TPSHKE U Post Anchor 4 Pk lists 3 mm (11 gauge), the AXWHYS 4×4 Post Base 4 Pk 13 gauge and the EONECROSS Adjustable Base 2 mm. Choose 11 or 13 gauge for tall pergola posts that catch wind.

Pack size

Count your posts before you order. Packs here range from 2 blocks with the Myard Deck Block 2 Pack to 10 with the BULLKE 10 in Pier Pads, EONECROSS Adjustable Base and Bullke Round Block 10 Pk. A 10 x 12 ft deck with posts about every 4 ft needs roughly 12 to 16 footings.

Codes and frost

Surface blocks do not reach below the frost line. Many codes limit them to freestanding decks and sheds. Check with your local building office, and follow each manufacturer’s instructions.

Which Cement Block for a 4×4 Post Should You Choose?

• If you want one block that handles most ground level jobs, choose the CAMO Deck Block 8 Pack, because it lists 1,800 lbs and takes 4×4 or 6×6 posts.
• If you prefer recycled plastic made in the USA, choose the BULLKE Handi Block, because it lists 1,750 lbs from 100% recycled plastic.
• If you want to stake each block to the ground, choose the Myard Deck Block 2 Pack, because it has 4 corner anchor holes and 5 screw holes.
• If you are pouring new footings, choose the TPSHKE U Post Anchor 4 Pk, because it uses 3 mm steel and M10 through bolts.
• If you want every screw and anchor in one box, choose the AXWHYS 4×4 Post Base 4 Pk, because it includes 24 concrete anchors and 24 wood screws.
• If load is your top concern, choose the BULLKE 10 in Pier Pads, because BULLKE lists up to 18,000 lbs per pad.
• If you are setting fence or railing posts, choose the Nrspp Wet Post Anchor 4 Pk, because it embeds 8 in and holds the post 6 in up.
• If you have many posts on a sloped slab, choose the EONECROSS Adjustable Base, because it comes 10 to a pack with an adjustable level.
• If you are replacing a few posts on a slab, choose the MIAOXY Galvanized Base 6 Pk, because it is galvanized with a 1 in standoff.
• If you need a low base under a shed beam, choose the Bullke Round Block 10 Pk, because it stands only 1 7/8 in tall.

Frequently Asked Questions

What is the best cement block for a 4×4 post?

For most ground level projects, the CAMO Deck Block 8 Pack is the best choice in this list. It lists a 1,800 lb load, takes 4×4 and 6×6 posts, and weighs 2.16 lbs, so one person can carry several. If your post goes on an existing slab, a steel base such as the AXWHYS 4×4 Post Base 4 Pk is a better fit.

Deck block vs post base: which do I need?

A deck block sits on gravel or soil and holds the post in a slot, so you need no concrete. A post base fixes the post to concrete, either set in a fresh pour like the TPSHKE U Post Anchor 4 Pk or bolted to a cured slab like the MIAOXY Galvanized Base 6 Pk. Pick a block for floating builds and a base where a slab or footing exists.

Can plastic deck blocks replace concrete blocks?

For many small, freestanding builds, yes. The CAMO Deck Block 8 Pack, BULLKE Handi Block and Myard Deck Block 2 Pack list loads of 1,700 to 1,800 lbs, and the CAMO and Myard blocks weigh about 2 lbs each, against about 50 lbs for concrete according to Myard. Check your local code, since some areas require poured footings below the frost line for attached decks.

How deep should a 4×4 post anchor sit in concrete?

Follow the anchor maker’s instructions. The Nrspp Wet Post Anchor 4 Pk is built to sit 8 in deep in wet concrete with 6 in above it. The TPSHKE U Post Anchor 4 Pk goes in until its H-shaped base is fully buried. Let the concrete cure as the bag label directs before you load the post.

Do I need to level the ground under a deck block?

Yes. Fixed-height blocks cannot correct a slope, and Bullke tells you to level the gravel or soil under its Bullke Round Block 10 Pk. Remove sod, tamp a gravel bed and check each spot with a level. On a slab, an adjustable base like the EONECROSS Adjustable Base can take up a slight tilt.

Is wet cement safe to handle when setting post anchors?

Wet cement is alkaline and can burn skin and eyes. Wear gloves, long sleeves and eye protection, and follow the safety notes on the concrete bag. Wash off any splashes with clean water right away, and keep children and pets away from fresh pours until they cure.

How many deck blocks do I need for a 4×4 post deck?

Plan one block under each post, spaced as your plans or local code require, often about 4 ft apart. The CAMO Deck Block 8 Pack comes 8 to a pack, the Myard Deck Block 2 Pack 2 to a pack and the BULLKE 10 in Pier Pads 10 to a pack, so round up to whole packs and buy a spare in case one sits badly.

Final Verdict

The CAMO Deck Block 8 Pack is the best cement block for 4×4 post projects that sit on the ground. It lists 1,800 lbs per block, takes 4×4 and 6×6 posts, and weighs just 2.16 lbs. If you are fixing posts to a finished slab, the AXWHYS 4×4 Post Base 4 Pk is the better pick thanks to its 24 concrete anchors and 24 wood screws. Before you buy, measure your posts and check your local code for footing rules.

See the CAMO Deck Block 8 Pack on Amazon