This WordPress plugin adds a multi-tiered flat rate shipping option for the WooCommerce plugin.

mhodges

WordPress administrators can create a multi-tiered flat rate shipping 
cost based on the total number of items in a WooCommerce cart. The 
store administrator can choose to apply this shipping method to all 
available countries or to specific countries.
This flexible shipping method provides up to 4 tiers, suitable for USPS 
flat-rate boxes. Also provided are several large-order shipping cost 
calculation methods for refining your total shipping costs calculations.
By default there are four tiers; 1, 2, 3, 4 – small to large. Tiers 3 
and 4 may be disabled if not needed.
<h3>Examples</h3>
One of the following examples may help you determine how best to 
configure the settings to get the results you require. Once you have 
saved your settings, be sure to look at the review table at the bottom 
of the settings page to confirm that your settings are calculating the 
shipping costs as anticipated.
Example 1
<ul>
<li>Default 4-Tier shipping method (all tiers enabled; suitable for USPS flat-rate)</li>
<li>Base cost: $0.00 (default)</li>
<li>Large Order Shipping Cost Calculation Method: prorate</li>
</ul>
<pre>
 Tier|Max Qty| Cost 
 ----+-------+------
 1 | 2 |$ 5.95
 2 | 4 |$12.65
 3 | 10 |$15.90
 4 | 15 |$17.90
 pro| each |$ 1.12
</pre>
Results
<ul>
<li>Shipping cost for 5 items = $15.90.</li>
<li>Shipping cost for 12 items = $17.90.</li>
<li>Shipping cost for 20 items = $17.90 + 5 x $1.12. Total cost is $23.50.</li>
</ul>
Example 2
<ul>
<li>Custom 3-Tier shipping method (tier 4 disabled)</li>
<li>Base cost: $0.00 (default)</li>
<li>Large Order Shipping Cost Calculation Method: prorate</li>
</ul>
<pre>
 Tier|Max Qty| Cost
 ----+-------+------
 1 | 10 |$ 7.00
 2 | 40 |$21.00
 3 | 160 |$42.00
 4 | disabled
 pro| each |$ 2.00
</pre>
Results
<ul>
<li>Shipping cost for 35 items = $21.00.</li>
<li>Shipping cost for 120 items = $42.00.</li>
<li>Prorated shipping cost for 200 items = $42.00 + 40 x $2.00. Total cost is $122.00.</li>
</ul>
Note
<ul>
<li>Disabling tier 3 and enabling tier 4 works results in exactly the same cost calculations.</li>
</ul>
Example 3
<ul>
<li>Default 4-Tier shipping method with free shipping for large orders.</li>
<li>Base cost: $2.00</li>
<li>Large Order Shipping Cost Calculation Method: prorate</li>
</ul>
<pre>
 Tier|Max Qty| Cost
 ----+-------+------
 1 | 15 |$ 5.00
 2 | 30 |$10.00
 3 | 45 |$15.00
 4 | 60 |$20.00
 pro| each |$ 0.00 < -- Large orders are free!!!
</pre>
Results
<ul>
<li>Shipping cost for 10 items = $ 5.00 + $2.00. Total cost is $ 7.00 including $2.00 base cost.</li>
<li>Shipping cost for 50 items = $20.00 + $2.00. Total cost is $22.00 including $2.00 base cost.</li>
<li>Shipping is free for orders greater than 60 items.</li>
</ul>
Example 4
<ul>
<li>Custom 2-Tier shipping method with free shipping (tiers 3 and 4 disabled) for large orders.</li>
<li>Base cost: $3.50</li>
<li>Large Order Shipping Cost Calculation Method: prorate</li>
</ul>
<pre>
 Tier|Max Qty| Cost
 ----+-------+------
 1 | 15 |$ 6.00
 2 | 30 |$10.00
 3 | disabled
 4 | disabled
 pro| each |$ 0.00 < -- Large orders are free!!!
</pre>
Results
<ul>
<li>Shipping cost for 16 items = $10.00 + $3.50. Total cost is $13.50 including $3.50 base cost.</li>
<li>Shipping is free for orders greater than 30 items.</li>
</ul>
<h3>Shipping Costs Preview</h3>
After updating and saving the settings, be sure to review the shipping 
costs calculations table provided at the bottom of the settings page. 
This will help you ensure that your settings achieve the desired 
calculations.
<h3>Updating Version 1.0 to Version 2.x</h3>
For those that are updating from version 1.0, there are new settings. The 
defaults ensure that there is no change to the shipping cost calculations 
that you have already set up.

CFD Multi-Tiered Shipping For WooCommerce

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